drivers/net/wireless/iwlwifi/iwl-agn-rs.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2005 - 2009 Intel Corporation. All rights reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  17  *
  18  * The full GNU General Public License is included in this distribution in the
  19  * file called LICENSE.
  20  *
  21  * Contact Information:
  22  *  Intel Linux Wireless <ilw@linux.intel.com>
  23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  24  *
  25  *****************************************************************************/
  26 #include <linux/kernel.h>
  27 #include <linux/init.h>
  28 #include <linux/skbuff.h>
  29 #include <linux/wireless.h>
  30 #include <net/mac80211.h>
  31
  32 #include <linux/netdevice.h>
  33 #include <linux/etherdevice.h>
  34 #include <linux/delay.h>
  35
  36 #include <linux/workqueue.h>
  37
  38 #include "iwl-dev.h"
  39 #include "iwl-sta.h"
  40 #include "iwl-core.h"
  41
  42 #define RS_NAME "iwl-agn-rs"
  43
  44 #define NUM_TRY_BEFORE_ANT_TOGGLE 1
  45 #define IWL_NUMBER_TRY      1
  46 #define IWL_HT_NUMBER_TRY   3
  47
  48 #define IWL_RATE_MAX_WINDOW             62      /* # tx in history window */
  49 #define IWL_RATE_MIN_FAILURE_TH         6       /* min failures to calc tpt */
  50 #define IWL_RATE_MIN_SUCCESS_TH         8       /* min successes to calc tpt */
  51
  52 /* max allowed rate miss before sync LQ cmd */
  53 #define IWL_MISSED_RATE_MAX             15
  54 /* max time to accum history 2 seconds */
  55 #define IWL_RATE_SCALE_FLUSH_INTVL   (3*HZ)
  56
  57 static u8 rs_ht_to_legacy[] = {
  58         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  59         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  60         IWL_RATE_6M_INDEX,
  61         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
  62         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
  63         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
  64         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
  65 };
  66
  67 static const u8 ant_toggle_lookup[] = {
  68         /*ANT_NONE -> */ ANT_NONE,
  69         /*ANT_A    -> */ ANT_B,
  70         /*ANT_B    -> */ ANT_C,
  71         /*ANT_AB   -> */ ANT_BC,
  72         /*ANT_C    -> */ ANT_A,
  73         /*ANT_AC   -> */ ANT_AB,
  74         /*ANT_BC   -> */ ANT_AC,
  75         /*ANT_ABC  -> */ ANT_ABC,
  76 };
  77
  78 /**
  79  * struct iwl_rate_scale_data -- tx success history for one rate
  80  */
  81 struct iwl_rate_scale_data {
  82         u64 data;               /* bitmap of successful frames */
  83         s32 success_counter;    /* number of frames successful */
  84         s32 success_ratio;      /* per-cent * 128  */
  85         s32 counter;            /* number of frames attempted */
  86         s32 average_tpt;        /* success ratio * expected throughput */
  87         unsigned long stamp;
  88 };
  89
  90 /**
  91  * struct iwl_scale_tbl_info -- tx params and success history for all rates
  92  *
  93  * There are two of these in struct iwl_lq_sta,
  94  * one for "active", and one for "search".
  95  */
  96 struct iwl_scale_tbl_info {
  97         enum iwl_table_type lq_type;
  98         u8 ant_type;
  99         u8 is_SGI;      /* 1 = short guard interval */
 100         u8 is_ht40;     /* 1 = 40 MHz channel width */
 101         u8 is_dup;      /* 1 = duplicated data streams */
 102         u8 action;      /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
 103         u8 max_search;  /* maximun number of tables we can search */
 104         s32 *expected_tpt;      /* throughput metrics; expected_tpt_G, etc. */
 105         u32 current_rate;  /* rate_n_flags, uCode API format */
 106         struct iwl_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
 107 };
 108
 109 struct iwl_traffic_load {
 110         unsigned long time_stamp;       /* age of the oldest statistics */
 111         u32 packet_count[TID_QUEUE_MAX_SIZE];   /* packet count in this time
 112                                                  * slice */
 113         u32 total;                      /* total num of packets during the
 114                                          * last TID_MAX_TIME_DIFF */
 115         u8 queue_count;                 /* number of queues that has
 116                                          * been used since the last cleanup */
 117         u8 head;                        /* start of the circular buffer */
 118 };
 119
 120 /**
 121  * struct iwl_lq_sta -- driver's rate scaling private structure
 122  *
 123  * Pointer to this gets passed back and forth between driver and mac80211.
 124  */
 125 struct iwl_lq_sta {
 126         u8 active_tbl;          /* index of active table, range 0-1 */
 127         u8 enable_counter;      /* indicates HT mode */
 128         u8 stay_in_tbl;         /* 1: disallow, 0: allow search for new mode */
 129         u8 search_better_tbl;   /* 1: currently trying alternate mode */
 130         s32 last_tpt;
 131
 132         /* The following determine when to search for a new mode */
 133         u32 table_count_limit;
 134         u32 max_failure_limit;  /* # failed frames before new search */
 135         u32 max_success_limit;  /* # successful frames before new search */
 136         u32 table_count;
 137         u32 total_failed;       /* total failed frames, any/all rates */
 138         u32 total_success;      /* total successful frames, any/all rates */
 139         u64 flush_timer;        /* time staying in mode before new search */
 140
 141         u8 action_counter;      /* # mode-switch actions tried */
 142         u8 is_green;
 143         u8 is_dup;
 144         enum ieee80211_band band;
 145         u8 ibss_sta_added;
 146
 147         /* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
 148         u32 supp_rates;
 149         u16 active_legacy_rate;
 150         u16 active_siso_rate;
 151         u16 active_mimo2_rate;
 152         u16 active_mimo3_rate;
 153         u16 active_rate_basic;
 154         s8 max_rate_idx;     /* Max rate set by user */
 155         u8 missed_rate_counter;
 156
 157         struct iwl_link_quality_cmd lq;
 158         struct iwl_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
 159         struct iwl_traffic_load load[TID_MAX_LOAD_COUNT];
 160         u8 tx_agg_tid_en;
 161 #ifdef CONFIG_MAC80211_DEBUGFS
 162         struct dentry *rs_sta_dbgfs_scale_table_file;
 163         struct dentry *rs_sta_dbgfs_stats_table_file;
 164         struct dentry *rs_sta_dbgfs_rate_scale_data_file;
 165         struct dentry *rs_sta_dbgfs_tx_agg_tid_en_file;
 166         u32 dbg_fixed_rate;
 167 #endif
 168         struct iwl_priv *drv;
 169
 170         /* used to be in sta_info */
 171         int last_txrate_idx;
 172         /* last tx rate_n_flags */
 173         u32 last_rate_n_flags;
 174 };
 175
 176 static void rs_rate_scale_perform(struct iwl_priv *priv,
 177                                    struct sk_buff *skb,
 178                                    struct ieee80211_sta *sta,
 179                                    struct iwl_lq_sta *lq_sta);
 180 static void rs_fill_link_cmd(struct iwl_priv *priv,
 181                              struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
 182
 183
 184 #ifdef CONFIG_MAC80211_DEBUGFS
 185 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 186                              u32 *rate_n_flags, int index);
 187 #else
 188 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 189                              u32 *rate_n_flags, int index)
 190 {}
 191 #endif
 192
 193 /*
 194  * Expected throughput metrics for following rates:
 195  * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
 196  * "G" is the only table that supports CCK (the first 4 rates).
 197  */
 198
 199 static s32 expected_tpt_A[IWL_RATE_COUNT] = {
 200         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186, 186
 201 };
 202
 203 static s32 expected_tpt_G[IWL_RATE_COUNT] = {
 204         7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 186
 205 };
 206
 207 static s32 expected_tpt_siso20MHz[IWL_RATE_COUNT] = {
 208         0, 0, 0, 0, 42, 42, 76, 102, 124, 159, 183, 193, 202
 209 };
 210
 211 static s32 expected_tpt_siso20MHzSGI[IWL_RATE_COUNT] = {
 212         0, 0, 0, 0, 46, 46, 82, 110, 132, 168, 192, 202, 211
 213 };
 214
 215 static s32 expected_tpt_mimo2_20MHz[IWL_RATE_COUNT] = {
 216         0, 0, 0, 0, 74, 74, 123, 155, 179, 214, 236, 244, 251
 217 };
 218
 219 static s32 expected_tpt_mimo2_20MHzSGI[IWL_RATE_COUNT] = {
 220         0, 0, 0, 0, 81, 81, 131, 164, 188, 222, 243, 251, 257
 221 };
 222
 223 static s32 expected_tpt_siso40MHz[IWL_RATE_COUNT] = {
 224         0, 0, 0, 0, 77, 77, 127, 160, 184, 220, 242, 250, 257
 225 };
 226
 227 static s32 expected_tpt_siso40MHzSGI[IWL_RATE_COUNT] = {
 228         0, 0, 0, 0, 83, 83, 135, 169, 193, 229, 250, 257, 264
 229 };
 230
 231 static s32 expected_tpt_mimo2_40MHz[IWL_RATE_COUNT] = {
 232         0, 0, 0, 0, 123, 123, 182, 214, 235, 264, 279, 285, 289
 233 };
 234
 235 static s32 expected_tpt_mimo2_40MHzSGI[IWL_RATE_COUNT] = {
 236         0, 0, 0, 0, 131, 131, 191, 222, 242, 270, 284, 289, 293
 237 };
 238
 239 /* Expected throughput metric MIMO3 */
 240 static s32 expected_tpt_mimo3_20MHz[IWL_RATE_COUNT] = {
 241         0, 0, 0, 0, 99, 99, 153, 186, 208, 239, 256, 263, 268
 242 };
 243
 244 static s32 expected_tpt_mimo3_20MHzSGI[IWL_RATE_COUNT] = {
 245         0, 0, 0, 0, 106, 106, 162, 194, 215, 246, 262, 268, 273
 246 };
 247
 248 static s32 expected_tpt_mimo3_40MHz[IWL_RATE_COUNT] = {
 249         0, 0, 0, 0, 152, 152, 211, 239, 255, 279, 290, 294, 297
 250 };
 251
 252 static s32 expected_tpt_mimo3_40MHzSGI[IWL_RATE_COUNT] = {
 253         0, 0, 0, 0, 160, 160, 219, 245, 261, 284, 294, 297, 300
 254 };
 255
 256 /* mbps, mcs */
 257 const static struct iwl_rate_mcs_info iwl_rate_mcs[IWL_RATE_COUNT] = {
 258   {"1", ""},
 259   {"2", ""},
 260   {"5.5", ""},
 261   {"11", ""},
 262   {"6", "BPSK 1/2"},
 263   {"9", "BPSK 1/2"},
 264   {"12", "QPSK 1/2"},
 265   {"18", "QPSK 3/4"},
 266   {"24", "16QAM 1/2"},
 267   {"36", "16QAM 3/4"},
 268   {"48", "64QAM 2/3"},
 269   {"54", "64QAM 3/4"},
 270   {"60", "64QAM 5/6"}
 271 };
 272
 273 #define MCS_INDEX_PER_STREAM    (8)
 274
 275 static inline u8 rs_extract_rate(u32 rate_n_flags)
 276 {
 277         return (u8)(rate_n_flags & 0xFF);
 278 }
 279
 280 static void rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
 281 {
 282         window->data = 0;
 283         window->success_counter = 0;
 284         window->success_ratio = IWL_INVALID_VALUE;
 285         window->counter = 0;
 286         window->average_tpt = IWL_INVALID_VALUE;
 287         window->stamp = 0;
 288 }
 289
 290 static inline u8 rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
 291 {
 292         return (ant_type & valid_antenna) == ant_type;
 293 }
 294
 295 /*
 296  *      removes the old data from the statistics. All data that is older than
 297  *      TID_MAX_TIME_DIFF, will be deleted.
 298  */
 299 static void rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time)
 300 {
 301         /* The oldest age we want to keep */
 302         u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
 303
 304         while (tl->queue_count &&
 305                (tl->time_stamp < oldest_time)) {
 306                 tl->total -= tl->packet_count[tl->head];
 307                 tl->packet_count[tl->head] = 0;
 308                 tl->time_stamp += TID_QUEUE_CELL_SPACING;
 309                 tl->queue_count--;
 310                 tl->head++;
 311                 if (tl->head >= TID_QUEUE_MAX_SIZE)
 312                         tl->head = 0;
 313         }
 314 }
 315
 316 /*
 317  *      increment traffic load value for tid and also remove
 318  *      any old values if passed the certain time period
 319  */
 320 static u8 rs_tl_add_packet(struct iwl_lq_sta *lq_data,
 321                            struct ieee80211_hdr *hdr)
 322 {
 323         u32 curr_time = jiffies_to_msecs(jiffies);
 324         u32 time_diff;
 325         s32 index;
 326         struct iwl_traffic_load *tl = NULL;
 327         u8 tid;
 328
 329         if (ieee80211_is_data_qos(hdr->frame_control)) {
 330                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 331                 tid = qc[0] & 0xf;
 332         } else
 333                 return MAX_TID_COUNT;
 334
 335         tl = &lq_data->load[tid];
 336
 337         curr_time -= curr_time % TID_ROUND_VALUE;
 338
 339         /* Happens only for the first packet. Initialize the data */
 340         if (!(tl->queue_count)) {
 341                 tl->total = 1;
 342                 tl->time_stamp = curr_time;
 343                 tl->queue_count = 1;
 344                 tl->head = 0;
 345                 tl->packet_count[0] = 1;
 346                 return MAX_TID_COUNT;
 347         }
 348
 349         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 350         index = time_diff / TID_QUEUE_CELL_SPACING;
 351
 352         /* The history is too long: remove data that is older than */
 353         /* TID_MAX_TIME_DIFF */
 354         if (index >= TID_QUEUE_MAX_SIZE)
 355                 rs_tl_rm_old_stats(tl, curr_time);
 356
 357         index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
 358         tl->packet_count[index] = tl->packet_count[index] + 1;
 359         tl->total = tl->total + 1;
 360
 361         if ((index + 1) > tl->queue_count)
 362                 tl->queue_count = index + 1;
 363
 364         return tid;
 365 }
 366
 367 /*
 368         get the traffic load value for tid
 369 */
 370 static u32 rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid)
 371 {
 372         u32 curr_time = jiffies_to_msecs(jiffies);
 373         u32 time_diff;
 374         s32 index;
 375         struct iwl_traffic_load *tl = NULL;
 376
 377         if (tid >= TID_MAX_LOAD_COUNT)
 378                 return 0;
 379
 380         tl = &(lq_data->load[tid]);
 381
 382         curr_time -= curr_time % TID_ROUND_VALUE;
 383
 384         if (!(tl->queue_count))
 385                 return 0;
 386
 387         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 388         index = time_diff / TID_QUEUE_CELL_SPACING;
 389
 390         /* The history is too long: remove data that is older than */
 391         /* TID_MAX_TIME_DIFF */
 392         if (index >= TID_QUEUE_MAX_SIZE)
 393                 rs_tl_rm_old_stats(tl, curr_time);
 394
 395         return tl->total;
 396 }
 397
 398 static void rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
 399                                       struct iwl_lq_sta *lq_data, u8 tid,
 400                                       struct ieee80211_sta *sta)
 401 {
 402         if (rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
 403                 IWL_DEBUG_HT(priv, "Starting Tx agg: STA: %pM tid: %d\n",
 404                                 sta->addr, tid);
 405                 ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
 406         }
 407 }
 408
 409 static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
 410                               struct iwl_lq_sta *lq_data,
 411                               struct ieee80211_sta *sta)
 412 {
 413         if ((tid < TID_MAX_LOAD_COUNT))
 414                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 415         else if (tid == IWL_AGG_ALL_TID)
 416                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
 417                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 418 }
 419
 420 static inline int get_num_of_ant_from_rate(u32 rate_n_flags)
 421 {
 422         return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
 423                !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
 424                !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
 425 }
 426
 427 /**
 428  * rs_collect_tx_data - Update the success/failure sliding window
 429  *
 430  * We keep a sliding window of the last 62 packets transmitted
 431  * at this rate.  window->data contains the bitmask of successful
 432  * packets.
 433  */
 434 static int rs_collect_tx_data(struct iwl_rate_scale_data *windows,
 435                               int scale_index, s32 tpt, int retries,
 436                               int successes)
 437 {
 438         struct iwl_rate_scale_data *window = NULL;
 439         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
 440         s32 fail_count;
 441
 442         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
 443                 return -EINVAL;
 444
 445         /* Select data for current tx bit rate */
 446         window = &(windows[scale_index]);
 447
 448         /*
 449          * Keep track of only the latest 62 tx frame attempts in this rate's
 450          * history window; anything older isn't really relevant any more.
 451          * If we have filled up the sliding window, drop the oldest attempt;
 452          * if the oldest attempt (highest bit in bitmap) shows "success",
 453          * subtract "1" from the success counter (this is the main reason
 454          * we keep these bitmaps!).
 455          */
 456         while (retries > 0) {
 457                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
 458
 459                         /* remove earliest */
 460                         window->counter = IWL_RATE_MAX_WINDOW - 1;
 461
 462                         if (window->data & mask) {
 463                                 window->data &= ~mask;
 464                                 window->success_counter--;
 465                         }
 466                 }
 467
 468                 /* Increment frames-attempted counter */
 469                 window->counter++;
 470
 471                 /* Shift bitmap by one frame (throw away oldest history),
 472                  * OR in "1", and increment "success" if this
 473                  * frame was successful. */
 474                 window->data <<= 1;
 475                 if (successes > 0) {
 476                         window->success_counter++;
 477                         window->data |= 0x1;
 478                         successes--;
 479                 }
 480
 481                 retries--;
 482         }
 483
 484         /* Calculate current success ratio, avoid divide-by-0! */
 485         if (window->counter > 0)
 486                 window->success_ratio = 128 * (100 * window->success_counter)
 487                                         / window->counter;
 488         else
 489                 window->success_ratio = IWL_INVALID_VALUE;
 490
 491         fail_count = window->counter - window->success_counter;
 492
 493         /* Calculate average throughput, if we have enough history. */
 494         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
 495             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
 496                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
 497         else
 498                 window->average_tpt = IWL_INVALID_VALUE;
 499
 500         /* Tag this window as having been updated */
 501         window->stamp = jiffies;
 502
 503         return 0;
 504 }
 505
 506 /*
 507  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
 508  */
 509 /* FIXME:RS:remove this function and put the flags statically in the table */
 510 static u32 rate_n_flags_from_tbl(struct iwl_priv *priv,
 511                                  struct iwl_scale_tbl_info *tbl,
 512                                  int index, u8 use_green)
 513 {
 514         u32 rate_n_flags = 0;
 515
 516         if (is_legacy(tbl->lq_type)) {
 517                 rate_n_flags = iwl_rates[index].plcp;
 518                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
 519                         rate_n_flags |= RATE_MCS_CCK_MSK;
 520
 521         } else if (is_Ht(tbl->lq_type)) {
 522                 if (index > IWL_LAST_OFDM_RATE) {
 523                         IWL_ERR(priv, "Invalid HT rate index %d\n", index);
 524                         index = IWL_LAST_OFDM_RATE;
 525                 }
 526                 rate_n_flags = RATE_MCS_HT_MSK;
 527
 528                 if (is_siso(tbl->lq_type))
 529                         rate_n_flags |= iwl_rates[index].plcp_siso;
 530                 else if (is_mimo2(tbl->lq_type))
 531                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
 532                 else
 533                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
 534         } else {
 535                 IWL_ERR(priv, "Invalid tbl->lq_type %d\n", tbl->lq_type);
 536         }
 537
 538         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
 539                                                      RATE_MCS_ANT_ABC_MSK);
 540
 541         if (is_Ht(tbl->lq_type)) {
 542                 if (tbl->is_ht40) {
 543                         if (tbl->is_dup)
 544                                 rate_n_flags |= RATE_MCS_DUP_MSK;
 545                         else
 546                                 rate_n_flags |= RATE_MCS_HT40_MSK;
 547                 }
 548                 if (tbl->is_SGI)
 549                         rate_n_flags |= RATE_MCS_SGI_MSK;
 550
 551                 if (use_green) {
 552                         rate_n_flags |= RATE_MCS_GF_MSK;
 553                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
 554                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
 555                                 IWL_ERR(priv, "GF was set with SGI:SISO\n");
 556                         }
 557                 }
 558         }
 559         return rate_n_flags;
 560 }
 561
 562 /*
 563  * Interpret uCode API's rate_n_flags format,
 564  * fill "search" or "active" tx mode table.
 565  */
 566 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
 567                                     enum ieee80211_band band,
 568                                     struct iwl_scale_tbl_info *tbl,
 569                                     int *rate_idx)
 570 {
 571         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
 572         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
 573         u8 mcs;
 574
 575         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
 576
 577         if (*rate_idx  == IWL_RATE_INVALID) {
 578                 *rate_idx = -1;
 579                 return -EINVAL;
 580         }
 581         tbl->is_SGI = 0;        /* default legacy setup */
 582         tbl->is_ht40 = 0;
 583         tbl->is_dup = 0;
 584         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
 585         tbl->lq_type = LQ_NONE;
 586         tbl->max_search = IWL_MAX_SEARCH;
 587
 588         /* legacy rate format */
 589         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
 590                 if (num_of_ant == 1) {
 591                         if (band == IEEE80211_BAND_5GHZ)
 592                                 tbl->lq_type = LQ_A;
 593                         else
 594                                 tbl->lq_type = LQ_G;
 595                 }
 596         /* HT rate format */
 597         } else {
 598                 if (rate_n_flags & RATE_MCS_SGI_MSK)
 599                         tbl->is_SGI = 1;
 600
 601                 if ((rate_n_flags & RATE_MCS_HT40_MSK) ||
 602                     (rate_n_flags & RATE_MCS_DUP_MSK))
 603                         tbl->is_ht40 = 1;
 604
 605                 if (rate_n_flags & RATE_MCS_DUP_MSK)
 606                         tbl->is_dup = 1;
 607
 608                 mcs = rs_extract_rate(rate_n_flags);
 609
 610                 /* SISO */
 611                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
 612                         if (num_of_ant == 1)
 613                                 tbl->lq_type = LQ_SISO; /*else NONE*/
 614                 /* MIMO2 */
 615                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
 616                         if (num_of_ant == 2)
 617                                 tbl->lq_type = LQ_MIMO2;
 618                 /* MIMO3 */
 619                 } else {
 620                         if (num_of_ant == 3) {
 621                                 tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
 622                                 tbl->lq_type = LQ_MIMO3;
 623                         }
 624                 }
 625         }
 626         return 0;
 627 }
 628
 629 /* switch to another antenna/antennas and return 1 */
 630 /* if no other valid antenna found, return 0 */
 631 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
 632                              struct iwl_scale_tbl_info *tbl)
 633 {
 634         u8 new_ant_type;
 635
 636         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
 637                 return 0;
 638
 639         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
 640                 return 0;
 641
 642         new_ant_type = ant_toggle_lookup[tbl->ant_type];
 643
 644         while ((new_ant_type != tbl->ant_type) &&
 645                !rs_is_valid_ant(valid_ant, new_ant_type))
 646                 new_ant_type = ant_toggle_lookup[new_ant_type];
 647
 648         if (new_ant_type == tbl->ant_type)
 649                 return 0;
 650
 651         tbl->ant_type = new_ant_type;
 652         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
 653         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
 654         return 1;
 655 }
 656
 657 /* in 4965 we don't use greenfield at all */
 658 static inline u8 rs_use_green(struct iwl_priv *priv,
 659                               struct ieee80211_conf *conf)
 660 {
 661         u8 is_green;
 662
 663         if ((priv->hw_rev & CSR_HW_REV_TYPE_MSK) == CSR_HW_REV_TYPE_4965)
 664                 is_green = 0;
 665         else
 666                 is_green = (conf_is_ht(conf) &&
 667                            priv->current_ht_config.is_green_field &&
 668                            !priv->current_ht_config.non_GF_STA_present);
 669         return is_green;
 670 }
 671
 672 /**
 673  * rs_get_supported_rates - get the available rates
 674  *
 675  * if management frame or broadcast frame only return
 676  * basic available rates.
 677  *
 678  */
 679 static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
 680                                   struct ieee80211_hdr *hdr,
 681                                   enum iwl_table_type rate_type)
 682 {
 683         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
 684             lq_sta->active_rate_basic)
 685                 return lq_sta->active_rate_basic;
 686
 687         if (is_legacy(rate_type)) {
 688                 return lq_sta->active_legacy_rate;
 689         } else {
 690                 if (is_siso(rate_type))
 691                         return lq_sta->active_siso_rate;
 692                 else if (is_mimo2(rate_type))
 693                         return lq_sta->active_mimo2_rate;
 694                 else
 695                         return lq_sta->active_mimo3_rate;
 696         }
 697 }
 698
 699 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
 700                                 int rate_type)
 701 {
 702         u8 high = IWL_RATE_INVALID;
 703         u8 low = IWL_RATE_INVALID;
 704
 705         /* 802.11A or ht walks to the next literal adjacent rate in
 706          * the rate table */
 707         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
 708                 int i;
 709                 u32 mask;
 710
 711                 /* Find the previous rate that is in the rate mask */
 712                 i = index - 1;
 713                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
 714                         if (rate_mask & mask) {
 715                                 low = i;
 716                                 break;
 717                         }
 718                 }
 719
 720                 /* Find the next rate that is in the rate mask */
 721                 i = index + 1;
 722                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
 723                         if (rate_mask & mask) {
 724                                 high = i;
 725                                 break;
 726                         }
 727                 }
 728
 729                 return (high << 8) | low;
 730         }
 731
 732         low = index;
 733         while (low != IWL_RATE_INVALID) {
 734                 low = iwl_rates[low].prev_rs;
 735                 if (low == IWL_RATE_INVALID)
 736                         break;
 737                 if (rate_mask & (1 << low))
 738                         break;
 739                 IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
 740         }
 741
 742         high = index;
 743         while (high != IWL_RATE_INVALID) {
 744                 high = iwl_rates[high].next_rs;
 745                 if (high == IWL_RATE_INVALID)
 746                         break;
 747                 if (rate_mask & (1 << high))
 748                         break;
 749                 IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
 750         }
 751
 752         return (high << 8) | low;
 753 }
 754
 755 static u32 rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
 756                              struct iwl_scale_tbl_info *tbl,
 757                              u8 scale_index, u8 ht_possible)
 758 {
 759         s32 low;
 760         u16 rate_mask;
 761         u16 high_low;
 762         u8 switch_to_legacy = 0;
 763         u8 is_green = lq_sta->is_green;
 764
 765         /* check if we need to switch from HT to legacy rates.
 766          * assumption is that mandatory rates (1Mbps or 6Mbps)
 767          * are always supported (spec demand) */
 768         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
 769                 switch_to_legacy = 1;
 770                 scale_index = rs_ht_to_legacy[scale_index];
 771                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 772                         tbl->lq_type = LQ_A;
 773                 else
 774                         tbl->lq_type = LQ_G;
 775
 776                 if (num_of_ant(tbl->ant_type) > 1)
 777                         tbl->ant_type = ANT_A;/*FIXME:RS*/
 778
 779                 tbl->is_ht40 = 0;
 780                 tbl->is_SGI = 0;
 781                 tbl->max_search = IWL_MAX_SEARCH;
 782         }
 783
 784         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
 785
 786         /* Mask with station rate restriction */
 787         if (is_legacy(tbl->lq_type)) {
 788                 /* supp_rates has no CCK bits in A mode */
 789                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 790                         rate_mask  = (u16)(rate_mask &
 791                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
 792                 else
 793                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
 794         }
 795
 796         /* If we switched from HT to legacy, check current rate */
 797         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
 798                 low = scale_index;
 799                 goto out;
 800         }
 801
 802         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
 803                                         tbl->lq_type);
 804         low = high_low & 0xff;
 805
 806         if (low == IWL_RATE_INVALID)
 807                 low = scale_index;
 808
 809 out:
 810         return rate_n_flags_from_tbl(lq_sta->drv, tbl, low, is_green);
 811 }
 812
 813 /*
 814  * mac80211 sends us Tx status
 815  */
 816 static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
 817                          struct ieee80211_sta *sta, void *priv_sta,
 818                          struct sk_buff *skb)
 819 {
 820         int status;
 821         u8 retries;
 822         int rs_index, index = 0;
 823         struct iwl_lq_sta *lq_sta = priv_sta;
 824         struct iwl_link_quality_cmd *table;
 825         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 826         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
 827         struct ieee80211_hw *hw = priv->hw;
 828         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 829         struct iwl_rate_scale_data *window = NULL;
 830         struct iwl_rate_scale_data *search_win = NULL;
 831         u32 tx_rate;
 832         struct iwl_scale_tbl_info tbl_type;
 833         struct iwl_scale_tbl_info *curr_tbl, *search_tbl;
 834         u8 active_index = 0;
 835         s32 tpt = 0;
 836
 837         IWL_DEBUG_RATE_LIMIT(priv, "get frame ack response, update rate scale window\n");
 838
 839         if (!ieee80211_is_data(hdr->frame_control) ||
 840             info->flags & IEEE80211_TX_CTL_NO_ACK)
 841                 return;
 842
 843         /* This packet was aggregated but doesn't carry rate scale info */
 844         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 845             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 846                 return;
 847
 848         if (info->flags & IEEE80211_TX_STAT_AMPDU)
 849                 retries = 0;
 850         else
 851                 retries = info->status.rates[0].count - 1;
 852
 853         if (retries > 15)
 854                 retries = 15;
 855
 856         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
 857             !lq_sta->ibss_sta_added)
 858                 goto out;
 859
 860         table = &lq_sta->lq;
 861         active_index = lq_sta->active_tbl;
 862
 863         curr_tbl = &(lq_sta->lq_info[active_index]);
 864         search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
 865         window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
 866         search_win = (struct iwl_rate_scale_data *)&(search_tbl->win[0]);
 867
 868         /*
 869          * Ignore this Tx frame response if its initial rate doesn't match
 870          * that of latest Link Quality command.  There may be stragglers
 871          * from a previous Link Quality command, but we're no longer interested
 872          * in those; they're either from the "active" mode while we're trying
 873          * to check "search" mode, or a prior "search" mode after we've moved
 874          * to a new "search" mode (which might become the new "active" mode).
 875          */
 876         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 877         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 878         if (priv->band == IEEE80211_BAND_5GHZ)
 879                 rs_index -= IWL_FIRST_OFDM_RATE;
 880
 881         if ((info->status.rates[0].idx < 0) ||
 882             (tbl_type.is_SGI != !!(info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)) ||
 883             (tbl_type.is_ht40 != !!(info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) ||
 884             (tbl_type.is_dup != !!(info->status.rates[0].flags & IEEE80211_TX_RC_DUP_DATA)) ||
 885             (tbl_type.ant_type != info->antenna_sel_tx) ||
 886             (!!(tx_rate & RATE_MCS_HT_MSK) != !!(info->status.rates[0].flags & IEEE80211_TX_RC_MCS)) ||
 887             (!!(tx_rate & RATE_MCS_GF_MSK) != !!(info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)) ||
 888             (hw->wiphy->bands[priv->band]->bitrates[rs_index].bitrate !=
 889              hw->wiphy->bands[info->band]->bitrates[info->status.rates[0].idx].bitrate)) {
 890                 IWL_DEBUG_RATE(priv, "initial rate does not match 0x%x\n", tx_rate);
 891                 /* the last LQ command could failed so the LQ in ucode not
 892                  * the same in driver sync up
 893                  */
 894                 lq_sta->missed_rate_counter++;
 895                 if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) {
 896                         lq_sta->missed_rate_counter = 0;
 897                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
 898                 }
 899                 goto out;
 900         }
 901
 902         lq_sta->missed_rate_counter = 0;
 903         /* Update frame history window with "failure" for each Tx retry. */
 904         while (retries) {
 905                 /* Look up the rate and other info used for each tx attempt.
 906                  * Each tx attempt steps one entry deeper in the rate table. */
 907                 tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
 908                 rs_get_tbl_info_from_mcs(tx_rate, priv->band,
 909                                           &tbl_type, &rs_index);
 910
 911                 /* If type matches "search" table,
 912                  * add failure to "search" history */
 913                 if ((tbl_type.lq_type == search_tbl->lq_type) &&
 914                     (tbl_type.ant_type == search_tbl->ant_type) &&
 915                     (tbl_type.is_SGI == search_tbl->is_SGI)) {
 916                         if (search_tbl->expected_tpt)
 917                                 tpt = search_tbl->expected_tpt[rs_index];
 918                         else
 919                                 tpt = 0;
 920                         rs_collect_tx_data(search_win, rs_index, tpt, 1, 0);
 921
 922                 /* Else if type matches "current/active" table,
 923                  * add failure to "current/active" history */
 924                 } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 925                            (tbl_type.ant_type == curr_tbl->ant_type) &&
 926                            (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 927                         if (curr_tbl->expected_tpt)
 928                                 tpt = curr_tbl->expected_tpt[rs_index];
 929                         else
 930                                 tpt = 0;
 931                         rs_collect_tx_data(window, rs_index, tpt, 1, 0);
 932                 }
 933
 934                 /* If not searching for a new mode, increment failed counter
 935                  * ... this helps determine when to start searching again */
 936                 if (lq_sta->stay_in_tbl)
 937                         lq_sta->total_failed++;
 938                 --retries;
 939                 index++;
 940
 941         }
 942
 943         /*
 944          * Find (by rate) the history window to update with final Tx attempt;
 945          * if Tx was successful first try, use original rate,
 946          * else look up the rate that was, finally, successful.
 947          */
 948         tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
 949         lq_sta->last_rate_n_flags = tx_rate;
 950         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 951
 952         /* Update frame history window with "success" if Tx got ACKed ... */
 953         status = !!(info->flags & IEEE80211_TX_STAT_ACK);
 954
 955         /* If type matches "search" table,
 956          * add final tx status to "search" history */
 957         if ((tbl_type.lq_type == search_tbl->lq_type) &&
 958             (tbl_type.ant_type == search_tbl->ant_type) &&
 959             (tbl_type.is_SGI == search_tbl->is_SGI)) {
 960                 if (search_tbl->expected_tpt)
 961                         tpt = search_tbl->expected_tpt[rs_index];
 962                 else
 963                         tpt = 0;
 964                 if (info->flags & IEEE80211_TX_STAT_AMPDU)
 965                         rs_collect_tx_data(search_win, rs_index, tpt,
 966                                            info->status.ampdu_ack_len,
 967                                            info->status.ampdu_ack_map);
 968                 else
 969                         rs_collect_tx_data(search_win, rs_index, tpt,
 970                                            1, status);
 971         /* Else if type matches "current/active" table,
 972          * add final tx status to "current/active" history */
 973         } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 974                    (tbl_type.ant_type == curr_tbl->ant_type) &&
 975                    (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 976                 if (curr_tbl->expected_tpt)
 977                         tpt = curr_tbl->expected_tpt[rs_index];
 978                 else
 979                         tpt = 0;
 980                 if (info->flags & IEEE80211_TX_STAT_AMPDU)
 981                         rs_collect_tx_data(window, rs_index, tpt,
 982                                            info->status.ampdu_ack_len,
 983                                            info->status.ampdu_ack_map);
 984                 else
 985                         rs_collect_tx_data(window, rs_index, tpt,
 986                                            1, status);
 987         }
 988
 989         /* If not searching for new mode, increment success/failed counter
 990          * ... these help determine when to start searching again */
 991         if (lq_sta->stay_in_tbl) {
 992                 if (info->flags & IEEE80211_TX_STAT_AMPDU) {
 993                         lq_sta->total_success += info->status.ampdu_ack_map;
 994                         lq_sta->total_failed +=
 995                              (info->status.ampdu_ack_len - info->status.ampdu_ack_map);
 996                 } else {
 997                         if (status)
 998                                 lq_sta->total_success++;
 999                         else
1000                                 lq_sta->total_failed++;
1001                 }
1002         }
1003
1004         /* See if there's a better rate or modulation mode to try. */
1005         if (sta && sta->supp_rates[sband->band])
1006                 rs_rate_scale_perform(priv, skb, sta, lq_sta);
1007 out:
1008         return;
1009 }
1010
1011 /*
1012  * Begin a period of staying with a selected modulation mode.
1013  * Set "stay_in_tbl" flag to prevent any mode switches.
1014  * Set frame tx success limits according to legacy vs. high-throughput,
1015  * and reset overall (spanning all rates) tx success history statistics.
1016  * These control how long we stay using same modulation mode before
1017  * searching for a new mode.
1018  */
1019 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
1020                                  struct iwl_lq_sta *lq_sta)
1021 {
1022         IWL_DEBUG_RATE(priv, "we are staying in the same table\n");
1023         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
1024         if (is_legacy) {
1025                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
1026                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
1027                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
1028         } else {
1029                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
1030                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
1031                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
1032         }
1033         lq_sta->table_count = 0;
1034         lq_sta->total_failed = 0;
1035         lq_sta->total_success = 0;
1036         lq_sta->flush_timer = jiffies;
1037         lq_sta->action_counter = 0;
1038 }
1039
1040 /*
1041  * Find correct throughput table for given mode of modulation
1042  */
1043 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
1044                                       struct iwl_scale_tbl_info *tbl)
1045 {
1046         if (is_legacy(tbl->lq_type)) {
1047                 if (!is_a_band(tbl->lq_type))
1048                         tbl->expected_tpt = expected_tpt_G;
1049                 else
1050                         tbl->expected_tpt = expected_tpt_A;
1051         } else if (is_siso(tbl->lq_type)) {
1052                 if (tbl->is_ht40 && !lq_sta->is_dup)
1053                         if (tbl->is_SGI)
1054                                 tbl->expected_tpt = expected_tpt_siso40MHzSGI;
1055                         else
1056                                 tbl->expected_tpt = expected_tpt_siso40MHz;
1057                 else if (tbl->is_SGI)
1058                         tbl->expected_tpt = expected_tpt_siso20MHzSGI;
1059                 else
1060                         tbl->expected_tpt = expected_tpt_siso20MHz;
1061         } else if (is_mimo2(tbl->lq_type)) {
1062                 if (tbl->is_ht40 && !lq_sta->is_dup)
1063                         if (tbl->is_SGI)
1064                                 tbl->expected_tpt = expected_tpt_mimo2_40MHzSGI;
1065                         else
1066                                 tbl->expected_tpt = expected_tpt_mimo2_40MHz;
1067                 else if (tbl->is_SGI)
1068                         tbl->expected_tpt = expected_tpt_mimo2_20MHzSGI;
1069                 else
1070                         tbl->expected_tpt = expected_tpt_mimo2_20MHz;
1071         } else if (is_mimo3(tbl->lq_type)) {
1072                 if (tbl->is_ht40 && !lq_sta->is_dup)
1073                         if (tbl->is_SGI)
1074                                 tbl->expected_tpt = expected_tpt_mimo3_40MHzSGI;
1075                         else
1076                                 tbl->expected_tpt = expected_tpt_mimo3_40MHz;
1077                 else if (tbl->is_SGI)
1078                         tbl->expected_tpt = expected_tpt_mimo3_20MHzSGI;
1079                 else
1080                         tbl->expected_tpt = expected_tpt_mimo3_20MHz;
1081         } else
1082                 tbl->expected_tpt = expected_tpt_G;
1083 }
1084
1085 /*
1086  * Find starting rate for new "search" high-throughput mode of modulation.
1087  * Goal is to find lowest expected rate (under perfect conditions) that is
1088  * above the current measured throughput of "active" mode, to give new mode
1089  * a fair chance to prove itself without too many challenges.
1090  *
1091  * This gets called when transitioning to more aggressive modulation
1092  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1093  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1094  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1095  * bit rate will typically need to increase, but not if performance was bad.
1096  */
1097 static s32 rs_get_best_rate(struct iwl_priv *priv,
1098                             struct iwl_lq_sta *lq_sta,
1099                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1100                             u16 rate_mask, s8 index)
1101 {
1102         /* "active" values */
1103         struct iwl_scale_tbl_info *active_tbl =
1104             &(lq_sta->lq_info[lq_sta->active_tbl]);
1105         s32 active_sr = active_tbl->win[index].success_ratio;
1106         s32 active_tpt = active_tbl->expected_tpt[index];
1107
1108         /* expected "search" throughput */
1109         s32 *tpt_tbl = tbl->expected_tpt;
1110
1111         s32 new_rate, high, low, start_hi;
1112         u16 high_low;
1113         s8 rate = index;
1114
1115         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1116
1117         for (; ;) {
1118                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1119                                                 tbl->lq_type);
1120
1121                 low = high_low & 0xff;
1122                 high = (high_low >> 8) & 0xff;
1123
1124                 /*
1125                  * Lower the "search" bit rate, to give new "search" mode
1126                  * approximately the same throughput as "active" if:
1127                  *
1128                  * 1) "Active" mode has been working modestly well (but not
1129                  *    great), and expected "search" throughput (under perfect
1130                  *    conditions) at candidate rate is above the actual
1131                  *    measured "active" throughput (but less than expected
1132                  *    "active" throughput under perfect conditions).
1133                  * OR
1134                  * 2) "Active" mode has been working perfectly or very well
1135                  *    and expected "search" throughput (under perfect
1136                  *    conditions) at candidate rate is above expected
1137                  *    "active" throughput (under perfect conditions).
1138                  */
1139                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1140                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1141                       (active_sr <= IWL_RATE_HIGH_TH) &&
1142                       (tpt_tbl[rate] <= active_tpt))) ||
1143                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1144                      (tpt_tbl[rate] > active_tpt))) {
1145
1146                         /* (2nd or later pass)
1147                          * If we've already tried to raise the rate, and are
1148                          * now trying to lower it, use the higher rate. */
1149                         if (start_hi != IWL_RATE_INVALID) {
1150                                 new_rate = start_hi;
1151                                 break;
1152                         }
1153
1154                         new_rate = rate;
1155
1156                         /* Loop again with lower rate */
1157                         if (low != IWL_RATE_INVALID)
1158                                 rate = low;
1159
1160                         /* Lower rate not available, use the original */
1161                         else
1162                                 break;
1163
1164                 /* Else try to raise the "search" rate to match "active" */
1165                 } else {
1166                         /* (2nd or later pass)
1167                          * If we've already tried to lower the rate, and are
1168                          * now trying to raise it, use the lower rate. */
1169                         if (new_rate != IWL_RATE_INVALID)
1170                                 break;
1171
1172                         /* Loop again with higher rate */
1173                         else if (high != IWL_RATE_INVALID) {
1174                                 start_hi = high;
1175                                 rate = high;
1176
1177                         /* Higher rate not available, use the original */
1178                         } else {
1179                                 new_rate = rate;
1180                                 break;
1181                         }
1182                 }
1183         }
1184
1185         return new_rate;
1186 }
1187
1188 /*
1189  * Set up search table for MIMO2
1190  */
1191 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1192                              struct iwl_lq_sta *lq_sta,
1193                              struct ieee80211_conf *conf,
1194                              struct ieee80211_sta *sta,
1195                              struct iwl_scale_tbl_info *tbl, int index)
1196 {
1197         u16 rate_mask;
1198         s32 rate;
1199         s8 is_green = lq_sta->is_green;
1200
1201         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1202                 return -1;
1203
1204         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1205                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1206                 return -1;
1207
1208         /* Need both Tx chains/antennas to support MIMO */
1209         if (priv->hw_params.tx_chains_num < 2)
1210                 return -1;
1211
1212         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO2\n");
1213
1214         tbl->lq_type = LQ_MIMO2;
1215         tbl->is_dup = lq_sta->is_dup;
1216         tbl->action = 0;
1217         tbl->max_search = IWL_MAX_SEARCH;
1218         rate_mask = lq_sta->active_mimo2_rate;
1219
1220         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1221                 tbl->is_ht40 = 1;
1222         else
1223                 tbl->is_ht40 = 0;
1224
1225         /* FIXME: - don't toggle SGI here
1226         if (tbl->is_ht40) {
1227                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1228                         tbl->is_SGI = 1;
1229                 else
1230                         tbl->is_SGI = 0;
1231         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1232                 tbl->is_SGI = 1;
1233         else
1234                 tbl->is_SGI = 0;
1235         */
1236
1237         rs_set_expected_tpt_table(lq_sta, tbl);
1238
1239         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1240
1241         IWL_DEBUG_RATE(priv, "LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1242         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1243                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1244                                                 rate, rate_mask);
1245                 return -1;
1246         }
1247         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1248
1249         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1250                      tbl->current_rate, is_green);
1251         return 0;
1252 }
1253
1254 /*
1255  * Set up search table for MIMO3
1256  */
1257 static int rs_switch_to_mimo3(struct iwl_priv *priv,
1258                              struct iwl_lq_sta *lq_sta,
1259                              struct ieee80211_conf *conf,
1260                              struct ieee80211_sta *sta,
1261                              struct iwl_scale_tbl_info *tbl, int index)
1262 {
1263         u16 rate_mask;
1264         s32 rate;
1265         s8 is_green = lq_sta->is_green;
1266
1267         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1268                 return -1;
1269
1270         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1271                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1272                 return -1;
1273
1274         /* Need both Tx chains/antennas to support MIMO */
1275         if (priv->hw_params.tx_chains_num < 3)
1276                 return -1;
1277
1278         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO3\n");
1279
1280         tbl->lq_type = LQ_MIMO3;
1281         tbl->is_dup = lq_sta->is_dup;
1282         tbl->action = 0;
1283         tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
1284         rate_mask = lq_sta->active_mimo3_rate;
1285
1286         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1287                 tbl->is_ht40 = 1;
1288         else
1289                 tbl->is_ht40 = 0;
1290
1291         /* FIXME: - don't toggle SGI here
1292         if (tbl->is_ht40) {
1293                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1294                         tbl->is_SGI = 1;
1295                 else
1296                         tbl->is_SGI = 0;
1297         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1298                 tbl->is_SGI = 1;
1299         else
1300                 tbl->is_SGI = 0;
1301         */
1302
1303         rs_set_expected_tpt_table(lq_sta, tbl);
1304
1305         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1306
1307         IWL_DEBUG_RATE(priv, "LQ: MIMO3 best rate %d mask %X\n",
1308                 rate, rate_mask);
1309         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1310                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1311                                                 rate, rate_mask);
1312                 return -1;
1313         }
1314         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1315
1316         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1317                      tbl->current_rate, is_green);
1318         return 0;
1319 }
1320
1321 /*
1322  * Set up search table for SISO
1323  */
1324 static int rs_switch_to_siso(struct iwl_priv *priv,
1325                              struct iwl_lq_sta *lq_sta,
1326                              struct ieee80211_conf *conf,
1327                              struct ieee80211_sta *sta,
1328                              struct iwl_scale_tbl_info *tbl, int index)
1329 {
1330         u16 rate_mask;
1331         u8 is_green = lq_sta->is_green;
1332         s32 rate;
1333
1334         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1335                 return -1;
1336
1337         IWL_DEBUG_RATE(priv, "LQ: try to switch to SISO\n");
1338
1339         tbl->is_dup = lq_sta->is_dup;
1340         tbl->lq_type = LQ_SISO;
1341         tbl->action = 0;
1342         tbl->max_search = IWL_MAX_SEARCH;
1343         rate_mask = lq_sta->active_siso_rate;
1344
1345         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1346                 tbl->is_ht40 = 1;
1347         else
1348                 tbl->is_ht40 = 0;
1349
1350         /* FIXME: - don't toggle SGI here
1351         if (tbl->is_ht40) {
1352                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1353                         tbl->is_SGI = 1;
1354                 else
1355                         tbl->is_SGI = 0;
1356         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1357                 tbl->is_SGI = 1;
1358         else
1359                 tbl->is_SGI = 0;
1360         */
1361
1362         if (is_green)
1363                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1364
1365         rs_set_expected_tpt_table(lq_sta, tbl);
1366         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1367
1368         IWL_DEBUG_RATE(priv, "LQ: get best rate %d mask %X\n", rate, rate_mask);
1369         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1370                 IWL_DEBUG_RATE(priv, "can not switch with index %d rate mask %x\n",
1371                              rate, rate_mask);
1372                 return -1;
1373         }
1374         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1375         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1376                      tbl->current_rate, is_green);
1377         return 0;
1378 }
1379
1380 /*
1381  * Try to switch to new modulation mode from legacy
1382  */
1383 static int rs_move_legacy_other(struct iwl_priv *priv,
1384                                 struct iwl_lq_sta *lq_sta,
1385                                 struct ieee80211_conf *conf,
1386                                 struct ieee80211_sta *sta,
1387                                 int index)
1388 {
1389         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1390         struct iwl_scale_tbl_info *search_tbl =
1391                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1392         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1393         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1394                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1395         u8 start_action = tbl->action;
1396         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1397         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1398         int ret = 0;
1399         u8 update_search_tbl_counter = 0;
1400
1401         if (!iwl_ht_enabled(priv))
1402                 /* stay in Legacy */
1403                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1404         else if (iwl_tx_ant_restriction(priv) == IWL_TX_SINGLE &&
1405                    tbl->action > IWL_LEGACY_SWITCH_SISO)
1406                 tbl->action = IWL_LEGACY_SWITCH_SISO;
1407         for (; ;) {
1408                 lq_sta->action_counter++;
1409                 switch (tbl->action) {
1410                 case IWL_LEGACY_SWITCH_ANTENNA1:
1411                 case IWL_LEGACY_SWITCH_ANTENNA2:
1412                         IWL_DEBUG_RATE(priv, "LQ: Legacy toggle Antenna\n");
1413
1414                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1415                                                         tx_chains_num <= 1) ||
1416                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1417                                                         tx_chains_num <= 2))
1418                                 break;
1419
1420                         /* Don't change antenna if success has been great */
1421                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1422                                 break;
1423
1424                         /* Set up search table to try other antenna */
1425                         memcpy(search_tbl, tbl, sz);
1426
1427                         if (rs_toggle_antenna(valid_tx_ant,
1428                                 &search_tbl->current_rate, search_tbl)) {
1429                                 update_search_tbl_counter = 1;
1430                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1431                                 goto out;
1432                         }
1433                         break;
1434                 case IWL_LEGACY_SWITCH_SISO:
1435                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to SISO\n");
1436
1437                         /* Set up search table to try SISO */
1438                         memcpy(search_tbl, tbl, sz);
1439                         search_tbl->is_SGI = 0;
1440                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1441                                                  search_tbl, index);
1442                         if (!ret) {
1443                                 lq_sta->action_counter = 0;
1444                                 goto out;
1445                         }
1446
1447                         break;
1448                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1449                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1450                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1451                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO2\n");
1452
1453                         /* Set up search table to try MIMO */
1454                         memcpy(search_tbl, tbl, sz);
1455                         search_tbl->is_SGI = 0;
1456
1457                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1458                                 search_tbl->ant_type = ANT_AB;
1459                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1460                                 search_tbl->ant_type = ANT_AC;
1461                         else
1462                                 search_tbl->ant_type = ANT_BC;
1463
1464                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1465                                 break;
1466
1467                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1468                                                  search_tbl, index);
1469                         if (!ret) {
1470                                 lq_sta->action_counter = 0;
1471                                 goto out;
1472                         }
1473                         break;
1474
1475                 case IWL_LEGACY_SWITCH_MIMO3_ABC:
1476                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO3\n");
1477
1478                         /* Set up search table to try MIMO3 */
1479                         memcpy(search_tbl, tbl, sz);
1480                         search_tbl->is_SGI = 0;
1481
1482                         search_tbl->ant_type = ANT_ABC;
1483
1484                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1485                                 break;
1486
1487                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1488                                                  search_tbl, index);
1489                         if (!ret) {
1490                                 lq_sta->action_counter = 0;
1491                                 goto out;
1492                         }
1493                         break;
1494                 }
1495                 tbl->action++;
1496                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1497                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1498
1499                 if (tbl->action == start_action)
1500                         break;
1501
1502         }
1503         search_tbl->lq_type = LQ_NONE;
1504         return 0;
1505
1506 out:
1507         lq_sta->search_better_tbl = 1;
1508         tbl->action++;
1509         if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1510                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1511         if (update_search_tbl_counter)
1512                 search_tbl->action = tbl->action;
1513         return 0;
1514
1515 }
1516
1517 /*
1518  * Try to switch to new modulation mode from SISO
1519  */
1520 static int rs_move_siso_to_other(struct iwl_priv *priv,
1521                                  struct iwl_lq_sta *lq_sta,
1522                                  struct ieee80211_conf *conf,
1523                                  struct ieee80211_sta *sta, int index)
1524 {
1525         u8 is_green = lq_sta->is_green;
1526         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1527         struct iwl_scale_tbl_info *search_tbl =
1528                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1529         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1530         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1531                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1532         u8 start_action = tbl->action;
1533         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1534         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1535         u8 update_search_tbl_counter = 0;
1536         int ret;
1537
1538         if (iwl_tx_ant_restriction(priv) == IWL_TX_SINGLE &&
1539             tbl->action > IWL_SISO_SWITCH_ANTENNA2) {
1540                 /* stay in SISO */
1541                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1542         }
1543         for (;;) {
1544                 lq_sta->action_counter++;
1545                 switch (tbl->action) {
1546                 case IWL_SISO_SWITCH_ANTENNA1:
1547                 case IWL_SISO_SWITCH_ANTENNA2:
1548                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle Antenna\n");
1549
1550                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1551                                                         tx_chains_num <= 1) ||
1552                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1553                                                         tx_chains_num <= 2))
1554                                 break;
1555
1556                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1557                                 break;
1558
1559                         memcpy(search_tbl, tbl, sz);
1560                         if (rs_toggle_antenna(valid_tx_ant,
1561                                        &search_tbl->current_rate, search_tbl)) {
1562                                 update_search_tbl_counter = 1;
1563                                 goto out;
1564                         }
1565                         break;
1566                 case IWL_SISO_SWITCH_MIMO2_AB:
1567                 case IWL_SISO_SWITCH_MIMO2_AC:
1568                 case IWL_SISO_SWITCH_MIMO2_BC:
1569                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO2\n");
1570                         memcpy(search_tbl, tbl, sz);
1571                         search_tbl->is_SGI = 0;
1572
1573                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1574                                 search_tbl->ant_type = ANT_AB;
1575                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1576                                 search_tbl->ant_type = ANT_AC;
1577                         else
1578                                 search_tbl->ant_type = ANT_BC;
1579
1580                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1581                                 break;
1582
1583                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1584                                                  search_tbl, index);
1585                         if (!ret)
1586                                 goto out;
1587                         break;
1588                 case IWL_SISO_SWITCH_GI:
1589                         if (!tbl->is_ht40 &&
1590                                 !(priv->current_ht_config.sgf &
1591                                                 HT_SHORT_GI_20MHZ))
1592                                 break;
1593                         if (tbl->is_ht40 &&
1594                                 !(priv->current_ht_config.sgf &
1595                                                 HT_SHORT_GI_40MHZ))
1596                                 break;
1597
1598                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle SGI/NGI\n");
1599
1600                         memcpy(search_tbl, tbl, sz);
1601                         if (is_green) {
1602                                 if (!tbl->is_SGI)
1603                                         break;
1604                                 else
1605                                         IWL_ERR(priv,
1606                                                 "SGI was set in GF+SISO\n");
1607                         }
1608                         search_tbl->is_SGI = !tbl->is_SGI;
1609                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1610                         if (tbl->is_SGI) {
1611                                 s32 tpt = lq_sta->last_tpt / 100;
1612                                 if (tpt >= search_tbl->expected_tpt[index])
1613                                         break;
1614                         }
1615                         search_tbl->current_rate =
1616                                 rate_n_flags_from_tbl(priv, search_tbl,
1617                                                       index, is_green);
1618                         update_search_tbl_counter = 1;
1619                         goto out;
1620                 case IWL_SISO_SWITCH_MIMO3_ABC:
1621                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO3\n");
1622                         memcpy(search_tbl, tbl, sz);
1623                         search_tbl->is_SGI = 0;
1624                         search_tbl->ant_type = ANT_ABC;
1625
1626                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1627                                 break;
1628
1629                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1630                                                  search_tbl, index);
1631                         if (!ret)
1632                                 goto out;
1633                         break;
1634                 }
1635                 tbl->action++;
1636                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1637                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1638
1639                 if (tbl->action == start_action)
1640                         break;
1641         }
1642         search_tbl->lq_type = LQ_NONE;
1643         return 0;
1644
1645  out:
1646         lq_sta->search_better_tbl = 1;
1647         tbl->action++;
1648         if (tbl->action > IWL_SISO_SWITCH_MIMO3_ABC)
1649                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1650         if (update_search_tbl_counter)
1651                 search_tbl->action = tbl->action;
1652
1653         return 0;
1654 }
1655
1656 /*
1657  * Try to switch to new modulation mode from MIMO2
1658  */
1659 static int rs_move_mimo2_to_other(struct iwl_priv *priv,
1660                                  struct iwl_lq_sta *lq_sta,
1661                                  struct ieee80211_conf *conf,
1662                                  struct ieee80211_sta *sta, int index)
1663 {
1664         s8 is_green = lq_sta->is_green;
1665         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1666         struct iwl_scale_tbl_info *search_tbl =
1667                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1668         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1669         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1670                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1671         u8 start_action = tbl->action;
1672         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1673         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1674         u8 update_search_tbl_counter = 0;
1675         int ret;
1676
1677         if ((iwl_tx_ant_restriction(priv) == IWL_TX_SINGLE) &&
1678             (tbl->action < IWL_MIMO2_SWITCH_SISO_A ||
1679              tbl->action > IWL_MIMO2_SWITCH_SISO_C)) {
1680                 /* switch in SISO */
1681                 tbl->action = IWL_MIMO2_SWITCH_SISO_A;
1682         }
1683         for (;;) {
1684                 lq_sta->action_counter++;
1685                 switch (tbl->action) {
1686                 case IWL_MIMO2_SWITCH_ANTENNA1:
1687                 case IWL_MIMO2_SWITCH_ANTENNA2:
1688                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle Antennas\n");
1689
1690                         if (tx_chains_num <= 2)
1691                                 break;
1692
1693                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1694                                 break;
1695
1696                         memcpy(search_tbl, tbl, sz);
1697                         if (rs_toggle_antenna(valid_tx_ant,
1698                                        &search_tbl->current_rate, search_tbl)) {
1699                                 update_search_tbl_counter = 1;
1700                                 goto out;
1701                         }
1702                         break;
1703                 case IWL_MIMO2_SWITCH_SISO_A:
1704                 case IWL_MIMO2_SWITCH_SISO_B:
1705                 case IWL_MIMO2_SWITCH_SISO_C:
1706                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to SISO\n");
1707
1708                         /* Set up new search table for SISO */
1709                         memcpy(search_tbl, tbl, sz);
1710
1711                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1712                                 search_tbl->ant_type = ANT_A;
1713                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1714                                 search_tbl->ant_type = ANT_B;
1715                         else
1716                                 search_tbl->ant_type = ANT_C;
1717
1718                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1719                                 break;
1720
1721                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1722                                                  search_tbl, index);
1723                         if (!ret)
1724                                 goto out;
1725
1726                         break;
1727
1728                 case IWL_MIMO2_SWITCH_GI:
1729                         if (!tbl->is_ht40 &&
1730                                 !(priv->current_ht_config.sgf &
1731                                                 HT_SHORT_GI_20MHZ))
1732                                 break;
1733                         if (tbl->is_ht40 &&
1734                                 !(priv->current_ht_config.sgf &
1735                                                 HT_SHORT_GI_40MHZ))
1736                                 break;
1737
1738                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle SGI/NGI\n");
1739
1740                         /* Set up new search table for MIMO2 */
1741                         memcpy(search_tbl, tbl, sz);
1742                         search_tbl->is_SGI = !tbl->is_SGI;
1743                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1744                         /*
1745                          * If active table already uses the fastest possible
1746                          * modulation (dual stream with short guard interval),
1747                          * and it's working well, there's no need to look
1748                          * for a better type of modulation!
1749                          */
1750                         if (tbl->is_SGI) {
1751                                 s32 tpt = lq_sta->last_tpt / 100;
1752                                 if (tpt >= search_tbl->expected_tpt[index])
1753                                         break;
1754                         }
1755                         search_tbl->current_rate =
1756                                 rate_n_flags_from_tbl(priv, search_tbl,
1757                                                       index, is_green);
1758                         update_search_tbl_counter = 1;
1759                         goto out;
1760
1761                 case IWL_MIMO2_SWITCH_MIMO3_ABC:
1762                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to MIMO3\n");
1763                         memcpy(search_tbl, tbl, sz);
1764                         search_tbl->is_SGI = 0;
1765                         search_tbl->ant_type = ANT_ABC;
1766
1767                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1768                                 break;
1769
1770                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1771                                                  search_tbl, index);
1772                         if (!ret)
1773                                 goto out;
1774
1775                         break;
1776                 }
1777                 tbl->action++;
1778                 if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1779                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1780
1781                 if (tbl->action == start_action)
1782                         break;
1783         }
1784         search_tbl->lq_type = LQ_NONE;
1785         return 0;
1786  out:
1787         lq_sta->search_better_tbl = 1;
1788         tbl->action++;
1789         if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1790                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1791         if (update_search_tbl_counter)
1792                 search_tbl->action = tbl->action;
1793
1794         return 0;
1795
1796 }
1797
1798 /*
1799  * Try to switch to new modulation mode from MIMO3
1800  */
1801 static int rs_move_mimo3_to_other(struct iwl_priv *priv,
1802                                  struct iwl_lq_sta *lq_sta,
1803                                  struct ieee80211_conf *conf,
1804                                  struct ieee80211_sta *sta, int index)
1805 {
1806         s8 is_green = lq_sta->is_green;
1807         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1808         struct iwl_scale_tbl_info *search_tbl =
1809                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1810         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1811         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1812                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1813         u8 start_action = tbl->action;
1814         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1815         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1816         int ret;
1817         u8 update_search_tbl_counter = 0;
1818
1819         if ((iwl_tx_ant_restriction(priv) == IWL_TX_SINGLE) &&
1820             (tbl->action < IWL_MIMO3_SWITCH_SISO_A ||
1821              tbl->action > IWL_MIMO3_SWITCH_SISO_C)) {
1822                 /* switch in SISO */
1823                 tbl->action = IWL_MIMO3_SWITCH_SISO_A;
1824         }
1825         for (;;) {
1826                 lq_sta->action_counter++;
1827                 switch (tbl->action) {
1828                 case IWL_MIMO3_SWITCH_ANTENNA1:
1829                 case IWL_MIMO3_SWITCH_ANTENNA2:
1830                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle Antennas\n");
1831
1832                         if (tx_chains_num <= 3)
1833                                 break;
1834
1835                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1836                                 break;
1837
1838                         memcpy(search_tbl, tbl, sz);
1839                         if (rs_toggle_antenna(valid_tx_ant,
1840                                        &search_tbl->current_rate, search_tbl))
1841                                 goto out;
1842                         break;
1843                 case IWL_MIMO3_SWITCH_SISO_A:
1844                 case IWL_MIMO3_SWITCH_SISO_B:
1845                 case IWL_MIMO3_SWITCH_SISO_C:
1846                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to SISO\n");
1847
1848                         /* Set up new search table for SISO */
1849                         memcpy(search_tbl, tbl, sz);
1850
1851                         if (tbl->action == IWL_MIMO3_SWITCH_SISO_A)
1852                                 search_tbl->ant_type = ANT_A;
1853                         else if (tbl->action == IWL_MIMO3_SWITCH_SISO_B)
1854                                 search_tbl->ant_type = ANT_B;
1855                         else
1856                                 search_tbl->ant_type = ANT_C;
1857
1858                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1859                                 break;
1860
1861                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1862                                                  search_tbl, index);
1863                         if (!ret)
1864                                 goto out;
1865
1866                         break;
1867
1868                 case IWL_MIMO3_SWITCH_MIMO2_AB:
1869                 case IWL_MIMO3_SWITCH_MIMO2_AC:
1870                 case IWL_MIMO3_SWITCH_MIMO2_BC:
1871                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to MIMO2\n");
1872
1873                         memcpy(search_tbl, tbl, sz);
1874                         search_tbl->is_SGI = 0;
1875                         if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AB)
1876                                 search_tbl->ant_type = ANT_AB;
1877                         else if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AC)
1878                                 search_tbl->ant_type = ANT_AC;
1879                         else
1880                                 search_tbl->ant_type = ANT_BC;
1881
1882                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1883                                 break;
1884
1885                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1886                                                  search_tbl, index);
1887                         if (!ret)
1888                                 goto out;
1889
1890                         break;
1891
1892                 case IWL_MIMO3_SWITCH_GI:
1893                         if (!tbl->is_ht40 &&
1894                                 !(priv->current_ht_config.sgf &
1895                                                 HT_SHORT_GI_20MHZ))
1896                                 break;
1897                         if (tbl->is_ht40 &&
1898                                 !(priv->current_ht_config.sgf &
1899                                                 HT_SHORT_GI_40MHZ))
1900                                 break;
1901
1902                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle SGI/NGI\n");
1903
1904                         /* Set up new search table for MIMO */
1905                         memcpy(search_tbl, tbl, sz);
1906                         search_tbl->is_SGI = !tbl->is_SGI;
1907                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1908                         /*
1909                          * If active table already uses the fastest possible
1910                          * modulation (dual stream with short guard interval),
1911                          * and it's working well, there's no need to look
1912                          * for a better type of modulation!
1913                          */
1914                         if (tbl->is_SGI) {
1915                                 s32 tpt = lq_sta->last_tpt / 100;
1916                                 if (tpt >= search_tbl->expected_tpt[index])
1917                                         break;
1918                         }
1919                         search_tbl->current_rate =
1920                                 rate_n_flags_from_tbl(priv, search_tbl,
1921                                                       index, is_green);
1922                         update_search_tbl_counter = 1;
1923                         goto out;
1924                 }
1925                 tbl->action++;
1926                 if (tbl->action > IWL_MIMO3_SWITCH_GI)
1927                         tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1928
1929                 if (tbl->action == start_action)
1930                         break;
1931         }
1932         search_tbl->lq_type = LQ_NONE;
1933         return 0;
1934  out:
1935         lq_sta->search_better_tbl = 1;
1936         tbl->action++;
1937         if (tbl->action > IWL_MIMO3_SWITCH_GI)
1938                 tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1939         if (update_search_tbl_counter)
1940                 search_tbl->action = tbl->action;
1941
1942         return 0;
1943
1944 }
1945
1946 /*
1947  * Check whether we should continue using same modulation mode, or
1948  * begin search for a new mode, based on:
1949  * 1) # tx successes or failures while using this mode
1950  * 2) # times calling this function
1951  * 3) elapsed time in this mode (not used, for now)
1952  */
1953 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1954 {
1955         struct iwl_scale_tbl_info *tbl;
1956         int i;
1957         int active_tbl;
1958         int flush_interval_passed = 0;
1959         struct iwl_priv *priv;
1960
1961         priv = lq_sta->drv;
1962         active_tbl = lq_sta->active_tbl;
1963
1964         tbl = &(lq_sta->lq_info[active_tbl]);
1965
1966         /* If we've been disallowing search, see if we should now allow it */
1967         if (lq_sta->stay_in_tbl) {
1968
1969                 /* Elapsed time using current modulation mode */
1970                 if (lq_sta->flush_timer)
1971                         flush_interval_passed =
1972                         time_after(jiffies,
1973                                         (unsigned long)(lq_sta->flush_timer +
1974                                         IWL_RATE_SCALE_FLUSH_INTVL));
1975
1976                 /*
1977                  * Check if we should allow search for new modulation mode.
1978                  * If many frames have failed or succeeded, or we've used
1979                  * this same modulation for a long time, allow search, and
1980                  * reset history stats that keep track of whether we should
1981                  * allow a new search.  Also (below) reset all bitmaps and
1982                  * stats in active history.
1983                  */
1984                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1985                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1986                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1987                      && (flush_interval_passed))) {
1988                         IWL_DEBUG_RATE(priv, "LQ: stay is expired %d %d %d\n:",
1989                                      lq_sta->total_failed,
1990                                      lq_sta->total_success,
1991                                      flush_interval_passed);
1992
1993                         /* Allow search for new mode */
1994                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1995                         lq_sta->total_failed = 0;
1996                         lq_sta->total_success = 0;
1997                         lq_sta->flush_timer = 0;
1998
1999                 /*
2000                  * Else if we've used this modulation mode enough repetitions
2001                  * (regardless of elapsed time or success/failure), reset
2002                  * history bitmaps and rate-specific stats for all rates in
2003                  * active table.
2004                  */
2005                 } else {
2006                         lq_sta->table_count++;
2007                         if (lq_sta->table_count >=
2008                             lq_sta->table_count_limit) {
2009                                 lq_sta->table_count = 0;
2010
2011                                 IWL_DEBUG_RATE(priv, "LQ: stay in table clear win\n");
2012                                 for (i = 0; i < IWL_RATE_COUNT; i++)
2013                                         rs_rate_scale_clear_window(
2014                                                 &(tbl->win[i]));
2015                         }
2016                 }
2017
2018                 /* If transitioning to allow "search", reset all history
2019                  * bitmaps and stats in active table (this will become the new
2020                  * "search" table). */
2021                 if (!lq_sta->stay_in_tbl) {
2022                         for (i = 0; i < IWL_RATE_COUNT; i++)
2023                                 rs_rate_scale_clear_window(&(tbl->win[i]));
2024                 }
2025         }
2026 }
2027
2028 /*
2029  * setup rate table in uCode
2030  * return rate_n_flags as used in the table
2031  */
2032 static u32 rs_update_rate_tbl(struct iwl_priv *priv,
2033                                 struct iwl_lq_sta *lq_sta,
2034                                 struct iwl_scale_tbl_info *tbl,
2035                                 int index, u8 is_green)
2036 {
2037         u32 rate;
2038
2039         /* Update uCode's rate table. */
2040         rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2041         rs_fill_link_cmd(priv, lq_sta, rate);
2042         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2043
2044         return rate;
2045 }
2046
2047 /*
2048  * Do rate scaling and search for new modulation mode.
2049  */
2050 static void rs_rate_scale_perform(struct iwl_priv *priv,
2051                                   struct sk_buff *skb,
2052                                   struct ieee80211_sta *sta,
2053                                   struct iwl_lq_sta *lq_sta)
2054 {
2055         struct ieee80211_hw *hw = priv->hw;
2056         struct ieee80211_conf *conf = &hw->conf;
2057         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2058         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2059         int low = IWL_RATE_INVALID;
2060         int high = IWL_RATE_INVALID;
2061         int index;
2062         int i;
2063         struct iwl_rate_scale_data *window = NULL;
2064         int current_tpt = IWL_INVALID_VALUE;
2065         int low_tpt = IWL_INVALID_VALUE;
2066         int high_tpt = IWL_INVALID_VALUE;
2067         u32 fail_count;
2068         s8 scale_action = 0;
2069         u16 rate_mask;
2070         u8 update_lq = 0;
2071         struct iwl_scale_tbl_info *tbl, *tbl1;
2072         u16 rate_scale_index_msk = 0;
2073         u32 rate;
2074         u8 is_green = 0;
2075         u8 active_tbl = 0;
2076         u8 done_search = 0;
2077         u16 high_low;
2078         s32 sr;
2079         u8 tid = MAX_TID_COUNT;
2080         struct iwl_tid_data *tid_data;
2081
2082         IWL_DEBUG_RATE(priv, "rate scale calculate new rate for skb\n");
2083
2084         /* Send management frames and NO_ACK data using lowest rate. */
2085         /* TODO: this could probably be improved.. */
2086         if (!ieee80211_is_data(hdr->frame_control) ||
2087             info->flags & IEEE80211_TX_CTL_NO_ACK)
2088                 return;
2089
2090         if (!sta || !lq_sta)
2091                 return;
2092
2093         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
2094
2095         tid = rs_tl_add_packet(lq_sta, hdr);
2096
2097         /*
2098          * Select rate-scale / modulation-mode table to work with in
2099          * the rest of this function:  "search" if searching for better
2100          * modulation mode, or "active" if doing rate scaling within a mode.
2101          */
2102         if (!lq_sta->search_better_tbl)
2103                 active_tbl = lq_sta->active_tbl;
2104         else
2105                 active_tbl = 1 - lq_sta->active_tbl;
2106
2107         tbl = &(lq_sta->lq_info[active_tbl]);
2108         if (is_legacy(tbl->lq_type))
2109                 lq_sta->is_green = 0;
2110         else
2111                 lq_sta->is_green = rs_use_green(priv, conf);
2112         is_green = lq_sta->is_green;
2113
2114         /* current tx rate */
2115         index = lq_sta->last_txrate_idx;
2116
2117         IWL_DEBUG_RATE(priv, "Rate scale index %d for type %d\n", index,
2118                        tbl->lq_type);
2119
2120         /* rates available for this association, and for modulation mode */
2121         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
2122
2123         IWL_DEBUG_RATE(priv, "mask 0x%04X \n", rate_mask);
2124
2125         /* mask with station rate restriction */
2126         if (is_legacy(tbl->lq_type)) {
2127                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
2128                         /* supp_rates has no CCK bits in A mode */
2129                         rate_scale_index_msk = (u16) (rate_mask &
2130                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
2131                 else
2132                         rate_scale_index_msk = (u16) (rate_mask &
2133                                                       lq_sta->supp_rates);
2134
2135         } else
2136                 rate_scale_index_msk = rate_mask;
2137
2138         if (!rate_scale_index_msk)
2139                 rate_scale_index_msk = rate_mask;
2140
2141         if (!((1 << index) & rate_scale_index_msk)) {
2142                 IWL_ERR(priv, "Current Rate is not valid\n");
2143                 if (lq_sta->search_better_tbl) {
2144                         /* revert to active table if search table is not valid*/
2145                         tbl->lq_type = LQ_NONE;
2146                         lq_sta->search_better_tbl = 0;
2147                         tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2148                         /* get "active" rate info */
2149                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2150                         rate = rs_update_rate_tbl(priv, lq_sta,
2151                                                   tbl, index, is_green);
2152                 }
2153                 return;
2154         }
2155
2156         /* Get expected throughput table and history window for current rate */
2157         if (!tbl->expected_tpt) {
2158                 IWL_ERR(priv, "tbl->expected_tpt is NULL\n");
2159                 return;
2160         }
2161
2162         /* force user max rate if set by user */
2163         if ((lq_sta->max_rate_idx != -1) &&
2164             (lq_sta->max_rate_idx < index)) {
2165                 index = lq_sta->max_rate_idx;
2166                 update_lq = 1;
2167                 window = &(tbl->win[index]);
2168                 goto lq_update;
2169         }
2170
2171         window = &(tbl->win[index]);
2172
2173         /*
2174          * If there is not enough history to calculate actual average
2175          * throughput, keep analyzing results of more tx frames, without
2176          * changing rate or mode (bypass most of the rest of this function).
2177          * Set up new rate table in uCode only if old rate is not supported
2178          * in current association (use new rate found above).
2179          */
2180         fail_count = window->counter - window->success_counter;
2181         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
2182                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
2183                 IWL_DEBUG_RATE(priv, "LQ: still below TH. succ=%d total=%d "
2184                                "for index %d\n",
2185                                window->success_counter, window->counter, index);
2186
2187                 /* Can't calculate this yet; not enough history */
2188                 window->average_tpt = IWL_INVALID_VALUE;
2189
2190                 /* Should we stay with this modulation mode,
2191                  * or search for a new one? */
2192                 rs_stay_in_table(lq_sta);
2193
2194                 goto out;
2195         }
2196
2197         /* Else we have enough samples; calculate estimate of
2198          * actual average throughput */
2199
2200         BUG_ON(window->average_tpt != ((window->success_ratio *
2201                         tbl->expected_tpt[index] + 64) / 128));
2202
2203         /* If we are searching for better modulation mode, check success. */
2204         if (lq_sta->search_better_tbl &&
2205             (iwl_tx_ant_restriction(priv) == IWL_TX_MULTI)) {
2206                 /* If good success, continue using the "search" mode;
2207                  * no need to send new link quality command, since we're
2208                  * continuing to use the setup that we've been trying. */
2209                 if (window->average_tpt > lq_sta->last_tpt) {
2210
2211                         IWL_DEBUG_RATE(priv, "LQ: SWITCHING TO NEW TABLE "
2212                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2213                                         window->success_ratio,
2214                                         window->average_tpt,
2215                                         lq_sta->last_tpt);
2216
2217                         if (!is_legacy(tbl->lq_type))
2218                                 lq_sta->enable_counter = 1;
2219
2220                         /* Swap tables; "search" becomes "active" */
2221                         lq_sta->active_tbl = active_tbl;
2222                         current_tpt = window->average_tpt;
2223
2224                 /* Else poor success; go back to mode in "active" table */
2225                 } else {
2226
2227                         IWL_DEBUG_RATE(priv, "LQ: GOING BACK TO THE OLD TABLE "
2228                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2229                                         window->success_ratio,
2230                                         window->average_tpt,
2231                                         lq_sta->last_tpt);
2232
2233                         /* Nullify "search" table */
2234                         tbl->lq_type = LQ_NONE;
2235
2236                         /* Revert to "active" table */
2237                         active_tbl = lq_sta->active_tbl;
2238                         tbl = &(lq_sta->lq_info[active_tbl]);
2239
2240                         /* Revert to "active" rate and throughput info */
2241                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2242                         current_tpt = lq_sta->last_tpt;
2243
2244                         /* Need to set up a new rate table in uCode */
2245                         update_lq = 1;
2246                 }
2247
2248                 /* Either way, we've made a decision; modulation mode
2249                  * search is done, allow rate adjustment next time. */
2250                 lq_sta->search_better_tbl = 0;
2251                 done_search = 1;        /* Don't switch modes below! */
2252                 goto lq_update;
2253         }
2254
2255         /* (Else) not in search of better modulation mode, try for better
2256          * starting rate, while staying in this mode. */
2257         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
2258                                         tbl->lq_type);
2259         low = high_low & 0xff;
2260         high = (high_low >> 8) & 0xff;
2261
2262         /* If user set max rate, dont allow higher than user constrain */
2263         if ((lq_sta->max_rate_idx != -1) &&
2264             (lq_sta->max_rate_idx < high))
2265                 high = IWL_RATE_INVALID;
2266
2267         sr = window->success_ratio;
2268
2269         /* Collect measured throughputs for current and adjacent rates */
2270         current_tpt = window->average_tpt;
2271         if (low != IWL_RATE_INVALID)
2272                 low_tpt = tbl->win[low].average_tpt;
2273         if (high != IWL_RATE_INVALID)
2274                 high_tpt = tbl->win[high].average_tpt;
2275
2276         scale_action = 0;
2277
2278         /* Too many failures, decrease rate */
2279         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
2280                 IWL_DEBUG_RATE(priv, "decrease rate because of low success_ratio\n");
2281                 scale_action = -1;
2282
2283         /* No throughput measured yet for adjacent rates; try increase. */
2284         } else if ((low_tpt == IWL_INVALID_VALUE) &&
2285                    (high_tpt == IWL_INVALID_VALUE)) {
2286
2287                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
2288                         scale_action = 1;
2289                 else if (low != IWL_RATE_INVALID)
2290                         scale_action = 0;
2291         }
2292
2293         /* Both adjacent throughputs are measured, but neither one has better
2294          * throughput; we're using the best rate, don't change it! */
2295         else if ((low_tpt != IWL_INVALID_VALUE) &&
2296                  (high_tpt != IWL_INVALID_VALUE) &&
2297                  (low_tpt < current_tpt) &&
2298                  (high_tpt < current_tpt))
2299                 scale_action = 0;
2300
2301         /* At least one adjacent rate's throughput is measured,
2302          * and may have better performance. */
2303         else {
2304                 /* Higher adjacent rate's throughput is measured */
2305                 if (high_tpt != IWL_INVALID_VALUE) {
2306                         /* Higher rate has better throughput */
2307                         if (high_tpt > current_tpt &&
2308                                         sr >= IWL_RATE_INCREASE_TH) {
2309                                 scale_action = 1;
2310                         } else {
2311                                 scale_action = 0;
2312                         }
2313
2314                 /* Lower adjacent rate's throughput is measured */
2315                 } else if (low_tpt != IWL_INVALID_VALUE) {
2316                         /* Lower rate has better throughput */
2317                         if (low_tpt > current_tpt) {
2318                                 IWL_DEBUG_RATE(priv,
2319                                     "decrease rate because of low tpt\n");
2320                                 scale_action = -1;
2321                         } else if (sr >= IWL_RATE_INCREASE_TH) {
2322                                 scale_action = 1;
2323                         }
2324                 }
2325         }
2326
2327         /* Sanity check; asked for decrease, but success rate or throughput
2328          * has been good at old rate.  Don't change it. */
2329         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
2330                     ((sr > IWL_RATE_HIGH_TH) ||
2331                      (current_tpt > (100 * tbl->expected_tpt[low]))))
2332                 scale_action = 0;
2333         if (!iwl_ht_enabled(priv) && !is_legacy(tbl->lq_type))
2334                 scale_action = -1;
2335         if (iwl_tx_ant_restriction(priv) != IWL_TX_MULTI &&
2336                 (is_mimo2(tbl->lq_type) || is_mimo3(tbl->lq_type)))
2337                 scale_action = -1;
2338         switch (scale_action) {
2339         case -1:
2340                 /* Decrease starting rate, update uCode's rate table */
2341                 if (low != IWL_RATE_INVALID) {
2342                         update_lq = 1;
2343                         index = low;
2344                 }
2345
2346                 break;
2347         case 1:
2348                 /* Increase starting rate, update uCode's rate table */
2349                 if (high != IWL_RATE_INVALID) {
2350                         update_lq = 1;
2351                         index = high;
2352                 }
2353
2354                 break;
2355         case 0:
2356                 /* No change */
2357         default:
2358                 break;
2359         }
2360
2361         IWL_DEBUG_RATE(priv, "choose rate scale index %d action %d low %d "
2362                     "high %d type %d\n",
2363                      index, scale_action, low, high, tbl->lq_type);
2364
2365 lq_update:
2366         /* Replace uCode's rate table for the destination station. */
2367         if (update_lq)
2368                 rate = rs_update_rate_tbl(priv, lq_sta,
2369                                           tbl, index, is_green);
2370
2371         if (iwl_tx_ant_restriction(priv) == IWL_TX_MULTI) {
2372                 /* Should we stay with this modulation mode,
2373                  * or search for a new one? */
2374                 rs_stay_in_table(lq_sta);
2375         }
2376         /*
2377          * Search for new modulation mode if we're:
2378          * 1)  Not changing rates right now
2379          * 2)  Not just finishing up a search
2380          * 3)  Allowing a new search
2381          */
2382         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
2383                 /* Save current throughput to compare with "search" throughput*/
2384                 lq_sta->last_tpt = current_tpt;
2385
2386                 /* Select a new "search" modulation mode to try.
2387                  * If one is found, set up the new "search" table. */
2388                 if (is_legacy(tbl->lq_type))
2389                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
2390                 else if (is_siso(tbl->lq_type))
2391                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
2392                 else if (is_mimo2(tbl->lq_type))
2393                         rs_move_mimo2_to_other(priv, lq_sta, conf, sta, index);
2394                 else
2395                         rs_move_mimo3_to_other(priv, lq_sta, conf, sta, index);
2396
2397                 /* If new "search" mode was selected, set up in uCode table */
2398                 if (lq_sta->search_better_tbl) {
2399                         /* Access the "search" table, clear its history. */
2400                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
2401                         for (i = 0; i < IWL_RATE_COUNT; i++)
2402                                 rs_rate_scale_clear_window(&(tbl->win[i]));
2403
2404                         /* Use new "search" start rate */
2405                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2406
2407                         IWL_DEBUG_RATE(priv, "Switch current  mcs: %X index: %d\n",
2408                                      tbl->current_rate, index);
2409                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
2410                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2411                 } else
2412                         done_search = 1;
2413         }
2414
2415         if (done_search && !lq_sta->stay_in_tbl) {
2416                 /* If the "active" (non-search) mode was legacy,
2417                  * and we've tried switching antennas,
2418                  * but we haven't been able to try HT modes (not available),
2419                  * stay with best antenna legacy modulation for a while
2420                  * before next round of mode comparisons. */
2421                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2422                 if (is_legacy(tbl1->lq_type) && !conf_is_ht(conf) &&
2423                     lq_sta->action_counter > tbl1->max_search) {
2424                         IWL_DEBUG_RATE(priv, "LQ: STAY in legacy table\n");
2425                         rs_set_stay_in_table(priv, 1, lq_sta);
2426                 }
2427
2428                 /* If we're in an HT mode, and all 3 mode switch actions
2429                  * have been tried and compared, stay in this best modulation
2430                  * mode for a while before next round of mode comparisons. */
2431                 if (lq_sta->enable_counter &&
2432                     (lq_sta->action_counter >= tbl1->max_search) &&
2433                     iwl_ht_enabled(priv)) {
2434                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2435                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2436                             (tid != MAX_TID_COUNT)) {
2437                                 tid_data =
2438                                    &priv->stations[lq_sta->lq.sta_id].tid[tid];
2439                                 if (tid_data->agg.state == IWL_AGG_OFF) {
2440                                         IWL_DEBUG_RATE(priv,
2441                                                        "try to aggregate tid %d\n",
2442                                                        tid);
2443                                         rs_tl_turn_on_agg(priv, tid,
2444                                                           lq_sta, sta);
2445                                 }
2446                         }
2447                         rs_set_stay_in_table(priv, 0, lq_sta);
2448                 }
2449         }
2450
2451 out:
2452         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2453         i = index;
2454         lq_sta->last_txrate_idx = i;
2455
2456         return;
2457 }
2458
2459
2460 static void rs_initialize_lq(struct iwl_priv *priv,
2461                              struct ieee80211_conf *conf,
2462                              struct ieee80211_sta *sta,
2463                              struct iwl_lq_sta *lq_sta)
2464 {
2465         struct iwl_scale_tbl_info *tbl;
2466         int rate_idx;
2467         int i;
2468         u32 rate;
2469         u8 use_green = rs_use_green(priv, conf);
2470         u8 active_tbl = 0;
2471         u8 valid_tx_ant;
2472
2473         if (!sta || !lq_sta)
2474                 goto out;
2475
2476         i = lq_sta->last_txrate_idx;
2477
2478         if ((lq_sta->lq.sta_id == 0xff) &&
2479             (priv->iw_mode == NL80211_IFTYPE_ADHOC))
2480                 goto out;
2481
2482         valid_tx_ant = priv->hw_params.valid_tx_ant;
2483
2484         if (!lq_sta->search_better_tbl)
2485                 active_tbl = lq_sta->active_tbl;
2486         else
2487                 active_tbl = 1 - lq_sta->active_tbl;
2488
2489         tbl = &(lq_sta->lq_info[active_tbl]);
2490
2491         if ((i < 0) || (i >= IWL_RATE_COUNT))
2492                 i = 0;
2493
2494         rate = iwl_rates[i].plcp;
2495         tbl->ant_type = first_antenna(valid_tx_ant);
2496         rate |= tbl->ant_type << RATE_MCS_ANT_POS;
2497
2498         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2499                 rate |= RATE_MCS_CCK_MSK;
2500
2501         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2502         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2503             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2504
2505         rate = rate_n_flags_from_tbl(priv, tbl, rate_idx, use_green);
2506         tbl->current_rate = rate;
2507         rs_set_expected_tpt_table(lq_sta, tbl);
2508         rs_fill_link_cmd(NULL, lq_sta, rate);
2509         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2510  out:
2511         return;
2512 }
2513
2514 static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
2515                         struct ieee80211_tx_rate_control *txrc)
2516 {
2517
2518         struct sk_buff *skb = txrc->skb;
2519         struct ieee80211_supported_band *sband = txrc->sband;
2520         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2521         struct ieee80211_conf *conf = &priv->hw->conf;
2522         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2523         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2524         struct iwl_lq_sta *lq_sta = priv_sta;
2525         int rate_idx;
2526
2527         IWL_DEBUG_RATE_LIMIT(priv, "rate scale calculate new rate for skb\n");
2528
2529         /* Get max rate if user set max rate */
2530         if (lq_sta) {
2531                 lq_sta->max_rate_idx = txrc->max_rate_idx;
2532                 if ((sband->band == IEEE80211_BAND_5GHZ) &&
2533                     (lq_sta->max_rate_idx != -1))
2534                         lq_sta->max_rate_idx += IWL_FIRST_OFDM_RATE;
2535                 if ((lq_sta->max_rate_idx < 0) ||
2536                     (lq_sta->max_rate_idx >= IWL_RATE_COUNT))
2537                         lq_sta->max_rate_idx = -1;
2538         }
2539
2540         /* Send management frames and NO_ACK data using lowest rate. */
2541         if (rate_control_send_low(sta, priv_sta, txrc))
2542                 return;
2543
2544         rate_idx  = lq_sta->last_txrate_idx;
2545
2546         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
2547             !lq_sta->ibss_sta_added) {
2548                 u8 sta_id = iwl_find_station(priv, hdr->addr1);
2549
2550                 if (sta_id == IWL_INVALID_STATION) {
2551                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n",
2552                                        hdr->addr1);
2553                         sta_id = iwl_add_station(priv, hdr->addr1,
2554                                                 false, CMD_ASYNC, NULL);
2555                 }
2556                 if ((sta_id != IWL_INVALID_STATION)) {
2557                         lq_sta->lq.sta_id = sta_id;
2558                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2559                         lq_sta->ibss_sta_added = 1;
2560                         rs_initialize_lq(priv, conf, sta, lq_sta);
2561                 }
2562         }
2563
2564         if (lq_sta->last_rate_n_flags & RATE_MCS_HT_MSK) {
2565                 rate_idx -= IWL_FIRST_OFDM_RATE;
2566                 /* 6M and 9M shared same MCS index */
2567                 rate_idx = (rate_idx > 0) ? (rate_idx - 1) : 0;
2568                 if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2569                     IWL_RATE_MIMO3_6M_PLCP)
2570                         rate_idx = rate_idx + (2 * MCS_INDEX_PER_STREAM);
2571                 else if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2572                          IWL_RATE_MIMO2_6M_PLCP)
2573                         rate_idx = rate_idx + MCS_INDEX_PER_STREAM;
2574                 info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
2575                 if (lq_sta->last_rate_n_flags & RATE_MCS_SGI_MSK)
2576                         info->control.rates[0].flags |= IEEE80211_TX_RC_SHORT_GI;
2577                 if (lq_sta->last_rate_n_flags & RATE_MCS_DUP_MSK)
2578                         info->control.rates[0].flags |= IEEE80211_TX_RC_DUP_DATA;
2579                 if (lq_sta->last_rate_n_flags & RATE_MCS_HT40_MSK)
2580                         info->control.rates[0].flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
2581                 if (lq_sta->last_rate_n_flags & RATE_MCS_GF_MSK)
2582                         info->control.rates[0].flags |= IEEE80211_TX_RC_GREEN_FIELD;
2583         } else {
2584                 if (rate_idx < 0 || rate_idx > IWL_RATE_COUNT)
2585                         rate_idx = rate_lowest_index(sband, sta);
2586                 else if (sband->band == IEEE80211_BAND_5GHZ)
2587                         rate_idx -= IWL_FIRST_OFDM_RATE;
2588         }
2589         info->control.rates[0].idx = rate_idx;
2590
2591 }
2592
2593 static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2594                           gfp_t gfp)
2595 {
2596         struct iwl_lq_sta *lq_sta;
2597         struct iwl_priv *priv;
2598         int i, j;
2599
2600         priv = (struct iwl_priv *)priv_rate;
2601         IWL_DEBUG_RATE(priv, "create station rate scale window\n");
2602
2603         lq_sta = kzalloc(sizeof(struct iwl_lq_sta), gfp);
2604
2605         if (lq_sta == NULL)
2606                 return NULL;
2607         lq_sta->lq.sta_id = 0xff;
2608
2609
2610         for (j = 0; j < LQ_SIZE; j++)
2611                 for (i = 0; i < IWL_RATE_COUNT; i++)
2612                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2613
2614         return lq_sta;
2615 }
2616
2617 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
2618                          struct ieee80211_sta *sta, void *priv_sta)
2619 {
2620         int i, j;
2621         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2622         struct ieee80211_conf *conf = &priv->hw->conf;
2623         struct iwl_lq_sta *lq_sta = priv_sta;
2624         u16 mask_bit = 0;
2625         int count;
2626         int start_rate = 0;
2627
2628         lq_sta->flush_timer = 0;
2629         lq_sta->supp_rates = sta->supp_rates[sband->band];
2630         for (j = 0; j < LQ_SIZE; j++)
2631                 for (i = 0; i < IWL_RATE_COUNT; i++)
2632                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2633
2634         IWL_DEBUG_RATE(priv, "LQ: *** rate scale station global init ***\n");
2635         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2636          * the lowest or the highest rate.. Could consider using RSSI from
2637          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2638          * after assoc.. */
2639
2640         lq_sta->ibss_sta_added = 0;
2641         if (priv->iw_mode == NL80211_IFTYPE_AP) {
2642                 u8 sta_id = iwl_find_station(priv,
2643                                                                 sta->addr);
2644
2645                 /* for IBSS the call are from tasklet */
2646                 IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2647
2648                 if (sta_id == IWL_INVALID_STATION) {
2649                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2650                         sta_id = iwl_add_station(priv, sta->addr, false,
2651                                                 CMD_ASYNC, NULL);
2652                 }
2653                 if ((sta_id != IWL_INVALID_STATION)) {
2654                         lq_sta->lq.sta_id = sta_id;
2655                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2656                 }
2657                 /* FIXME: this is w/a remove it later */
2658                 priv->assoc_station_added = 1;
2659         }
2660
2661         lq_sta->is_dup = 0;
2662         lq_sta->max_rate_idx = -1;
2663         lq_sta->missed_rate_counter = IWL_MISSED_RATE_MAX;
2664         lq_sta->is_green = rs_use_green(priv, conf);
2665         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2666         lq_sta->active_rate_basic = priv->active_rate_basic;
2667         lq_sta->band = priv->band;
2668         /*
2669          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2670          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2671          */
2672         lq_sta->active_siso_rate = sta->ht_cap.mcs.rx_mask[0] << 1;
2673         lq_sta->active_siso_rate |= sta->ht_cap.mcs.rx_mask[0] & 0x1;
2674         lq_sta->active_siso_rate &= ~((u16)0x2);
2675         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2676
2677         /* Same here */
2678         lq_sta->active_mimo2_rate = sta->ht_cap.mcs.rx_mask[1] << 1;
2679         lq_sta->active_mimo2_rate |= sta->ht_cap.mcs.rx_mask[1] & 0x1;
2680         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2681         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2682
2683         lq_sta->active_mimo3_rate = sta->ht_cap.mcs.rx_mask[2] << 1;
2684         lq_sta->active_mimo3_rate |= sta->ht_cap.mcs.rx_mask[2] & 0x1;
2685         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2686         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2687
2688         IWL_DEBUG_RATE(priv, "SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2689                      lq_sta->active_siso_rate,
2690                      lq_sta->active_mimo2_rate,
2691                      lq_sta->active_mimo3_rate);
2692
2693         /* These values will be overridden later */
2694         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2695         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2696
2697         /* as default allow aggregation for all tids */
2698         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2699         lq_sta->drv = priv;
2700
2701         /* Find highest tx rate supported by hardware and destination station */
2702         mask_bit = sta->supp_rates[sband->band];
2703         count = sband->n_bitrates;
2704         if (sband->band == IEEE80211_BAND_5GHZ) {
2705                 count += IWL_FIRST_OFDM_RATE;
2706                 start_rate = IWL_FIRST_OFDM_RATE;
2707                 mask_bit <<= IWL_FIRST_OFDM_RATE;
2708         }
2709
2710         mask_bit = mask_bit & lq_sta->active_legacy_rate;
2711         lq_sta->last_txrate_idx = 4;
2712         for (i = start_rate; i < count; i++)
2713                 if (mask_bit & BIT(i))
2714                         lq_sta->last_txrate_idx = i;
2715
2716         rs_initialize_lq(priv, conf, sta, lq_sta);
2717 }
2718
2719 static void rs_fill_link_cmd(struct iwl_priv *priv,
2720                              struct iwl_lq_sta *lq_sta, u32 new_rate)
2721 {
2722         struct iwl_scale_tbl_info tbl_type;
2723         int index = 0;
2724         int rate_idx;
2725         int repeat_rate = 0;
2726         u8 ant_toggle_cnt = 0;
2727         u8 use_ht_possible = 1;
2728         u8 valid_tx_ant = 0;
2729         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2730
2731         /* Override starting rate (index 0) if needed for debug purposes */
2732         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2733
2734         /* Interpret new_rate (rate_n_flags) */
2735         memset(&tbl_type, 0, sizeof(tbl_type));
2736         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2737                                   &tbl_type, &rate_idx);
2738
2739         /* How many times should we repeat the initial rate? */
2740         if (is_legacy(tbl_type.lq_type)) {
2741                 ant_toggle_cnt = 1;
2742                 repeat_rate = IWL_NUMBER_TRY;
2743         } else {
2744                 repeat_rate = IWL_HT_NUMBER_TRY;
2745         }
2746
2747         lq_cmd->general_params.mimo_delimiter =
2748                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2749
2750         /* Fill 1st table entry (index 0) */
2751         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2752
2753         if (num_of_ant(tbl_type.ant_type) == 1) {
2754                 lq_cmd->general_params.single_stream_ant_msk =
2755                                                 tbl_type.ant_type;
2756         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2757                 lq_cmd->general_params.dual_stream_ant_msk =
2758                                                 tbl_type.ant_type;
2759         } /* otherwise we don't modify the existing value */
2760
2761         index++;
2762         repeat_rate--;
2763
2764         if (priv)
2765                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2766
2767         /* Fill rest of rate table */
2768         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2769                 /* Repeat initial/next rate.
2770                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2771                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2772                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2773                         if (is_legacy(tbl_type.lq_type)) {
2774                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2775                                         ant_toggle_cnt++;
2776                                 else if (priv &&
2777                                          rs_toggle_antenna(valid_tx_ant,
2778                                                         &new_rate, &tbl_type))
2779                                         ant_toggle_cnt = 1;
2780 }
2781
2782                         /* Override next rate if needed for debug purposes */
2783                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2784
2785                         /* Fill next table entry */
2786                         lq_cmd->rs_table[index].rate_n_flags =
2787                                         cpu_to_le32(new_rate);
2788                         repeat_rate--;
2789                         index++;
2790                 }
2791
2792                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2793                                                 &rate_idx);
2794
2795                 /* Indicate to uCode which entries might be MIMO.
2796                  * If initial rate was MIMO, this will finally end up
2797                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2798                 if (is_mimo(tbl_type.lq_type))
2799                         lq_cmd->general_params.mimo_delimiter = index;
2800
2801                 /* Get next rate */
2802                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2803                                              use_ht_possible);
2804
2805                 /* How many times should we repeat the next rate? */
2806                 if (is_legacy(tbl_type.lq_type)) {
2807                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2808                                 ant_toggle_cnt++;
2809                         else if (priv &&
2810                                  rs_toggle_antenna(valid_tx_ant,
2811                                                    &new_rate, &tbl_type))
2812                                 ant_toggle_cnt = 1;
2813
2814                         repeat_rate = IWL_NUMBER_TRY;
2815                 } else {
2816                         repeat_rate = IWL_HT_NUMBER_TRY;
2817                 }
2818
2819                 /* Don't allow HT rates after next pass.
2820                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2821                 use_ht_possible = 0;
2822
2823                 /* Override next rate if needed for debug purposes */
2824                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2825
2826                 /* Fill next table entry */
2827                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2828
2829                 index++;
2830                 repeat_rate--;
2831         }
2832
2833         lq_cmd->agg_params.agg_frame_cnt_limit = LINK_QUAL_AGG_FRAME_LIMIT_MAX;
2834         lq_cmd->agg_params.agg_dis_start_th = LINK_QUAL_AGG_DISABLE_START_DEF;
2835         lq_cmd->agg_params.agg_time_limit =
2836                 cpu_to_le16(LINK_QUAL_AGG_TIME_LIMIT_DEF);
2837 }
2838
2839 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2840 {
2841         return hw->priv;
2842 }
2843 /* rate scale requires free function to be implemented */
2844 static void rs_free(void *priv_rate)
2845 {
2846         return;
2847 }
2848
2849 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2850                         void *priv_sta)
2851 {
2852         struct iwl_lq_sta *lq_sta = priv_sta;
2853         struct iwl_priv *priv __maybe_unused = priv_r;
2854
2855         IWL_DEBUG_RATE(priv, "enter\n");
2856         kfree(lq_sta);
2857         IWL_DEBUG_RATE(priv, "leave\n");
2858 }
2859
2860
2861 #ifdef CONFIG_MAC80211_DEBUGFS
2862 static int open_file_generic(struct inode *inode, struct file *file)
2863 {
2864         file->private_data = inode->i_private;
2865         return 0;
2866 }
2867 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2868                              u32 *rate_n_flags, int index)
2869 {
2870         struct iwl_priv *priv;
2871         u8 valid_tx_ant;
2872         u8 ant_sel_tx;
2873
2874         priv = lq_sta->drv;
2875         valid_tx_ant = priv->hw_params.valid_tx_ant;
2876         if (lq_sta->dbg_fixed_rate) {
2877                 ant_sel_tx =
2878                   ((lq_sta->dbg_fixed_rate & RATE_MCS_ANT_ABC_MSK)
2879                   >> RATE_MCS_ANT_POS);
2880                 if ((valid_tx_ant & ant_sel_tx) == ant_sel_tx) {
2881                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2882                         IWL_DEBUG_RATE(priv, "Fixed rate ON\n");
2883                 } else {
2884                         lq_sta->dbg_fixed_rate = 0;
2885                         IWL_ERR(priv,
2886                             "Invalid antenna selection 0x%X, Valid is 0x%X\n",
2887                             ant_sel_tx, valid_tx_ant);
2888                         IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2889                 }
2890         } else {
2891                 IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2892         }
2893 }
2894
2895 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2896                         const char __user *user_buf, size_t count, loff_t *ppos)
2897 {
2898         struct iwl_lq_sta *lq_sta = file->private_data;
2899         struct iwl_priv *priv;
2900         char buf[64];
2901         int buf_size;
2902         u32 parsed_rate;
2903
2904         priv = lq_sta->drv;
2905         memset(buf, 0, sizeof(buf));
2906         buf_size = min(count, sizeof(buf) -  1);
2907         if (copy_from_user(buf, user_buf, buf_size))
2908                 return -EFAULT;
2909
2910         if (sscanf(buf, "%x", &parsed_rate) == 1)
2911                 lq_sta->dbg_fixed_rate = parsed_rate;
2912         else
2913                 lq_sta->dbg_fixed_rate = 0;
2914
2915         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2916         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2917         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2918         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2919
2920         IWL_DEBUG_RATE(priv, "sta_id %d rate 0x%X\n",
2921                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2922
2923         if (lq_sta->dbg_fixed_rate) {
2924                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2925                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2926         }
2927
2928         return count;
2929 }
2930
2931 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2932                         char __user *user_buf, size_t count, loff_t *ppos)
2933 {
2934         char *buff;
2935         int desc = 0;
2936         int i = 0;
2937         int index = 0;
2938         ssize_t ret;
2939
2940         struct iwl_lq_sta *lq_sta = file->private_data;
2941         struct iwl_priv *priv;
2942         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2943
2944         priv = lq_sta->drv;
2945         buff = kmalloc(1024, GFP_KERNEL);
2946         if (!buff)
2947                 return -ENOMEM;
2948
2949         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2950         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2951                         lq_sta->total_failed, lq_sta->total_success,
2952                         lq_sta->active_legacy_rate);
2953         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2954                         lq_sta->dbg_fixed_rate);
2955         desc += sprintf(buff+desc, "valid_tx_ant %s%s%s\n",
2956             (priv->hw_params.valid_tx_ant & ANT_A) ? "ANT_A," : "",
2957             (priv->hw_params.valid_tx_ant & ANT_B) ? "ANT_B," : "",
2958             (priv->hw_params.valid_tx_ant & ANT_C) ? "ANT_C" : "");
2959         desc += sprintf(buff+desc, "lq type %s\n",
2960            (is_legacy(tbl->lq_type)) ? "legacy" : "HT");
2961         if (is_Ht(tbl->lq_type)) {
2962                 desc += sprintf(buff+desc, " %s",
2963                    (is_siso(tbl->lq_type)) ? "SISO" :
2964                    ((is_mimo2(tbl->lq_type)) ? "MIMO2" : "MIMO3"));
2965                    desc += sprintf(buff+desc, " %s",
2966                    (tbl->is_ht40) ? "40MHz" : "20MHz");
2967                    desc += sprintf(buff+desc, " %s %s\n", (tbl->is_SGI) ? "SGI" : "",
2968                    (lq_sta->is_green) ? "GF enabled" : "");
2969         }
2970         desc += sprintf(buff+desc, "last tx rate=0x%X\n",
2971                 lq_sta->last_rate_n_flags);
2972         desc += sprintf(buff+desc, "general:"
2973                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2974                 lq_sta->lq.general_params.flags,
2975                 lq_sta->lq.general_params.mimo_delimiter,
2976                 lq_sta->lq.general_params.single_stream_ant_msk,
2977                 lq_sta->lq.general_params.dual_stream_ant_msk);
2978
2979         desc += sprintf(buff+desc, "agg:"
2980                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2981                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2982                         lq_sta->lq.agg_params.agg_dis_start_th,
2983                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2984
2985         desc += sprintf(buff+desc,
2986                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2987                         lq_sta->lq.general_params.start_rate_index[0],
2988                         lq_sta->lq.general_params.start_rate_index[1],
2989                         lq_sta->lq.general_params.start_rate_index[2],
2990                         lq_sta->lq.general_params.start_rate_index[3]);
2991
2992         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
2993                 index = iwl_hwrate_to_plcp_idx(
2994                         le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2995                 if (is_legacy(tbl->lq_type)) {
2996                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps\n",
2997                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2998                                 iwl_rate_mcs[index].mbps);
2999                 } else {
3000                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps (%s)\n",
3001                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
3002                                 iwl_rate_mcs[index].mbps, iwl_rate_mcs[index].mcs);
3003                 }
3004         }
3005
3006         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
3007         kfree(buff);
3008         return ret;
3009 }
3010
3011 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
3012         .write = rs_sta_dbgfs_scale_table_write,
3013         .read = rs_sta_dbgfs_scale_table_read,
3014         .open = open_file_generic,
3015 };
3016 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
3017                         char __user *user_buf, size_t count, loff_t *ppos)
3018 {
3019         char *buff;
3020         int desc = 0;
3021         int i, j;
3022         ssize_t ret;
3023
3024         struct iwl_lq_sta *lq_sta = file->private_data;
3025
3026         buff = kmalloc(1024, GFP_KERNEL);
3027         if (!buff)
3028                 return -ENOMEM;
3029
3030         for (i = 0; i < LQ_SIZE; i++) {
3031                 desc += sprintf(buff+desc,
3032                                 "%s type=%d SGI=%d HT40=%d DUP=%d GF=%d\n"
3033                                 "rate=0x%X\n",
3034                                 lq_sta->active_tbl == i ? "*" : "x",
3035                                 lq_sta->lq_info[i].lq_type,
3036                                 lq_sta->lq_info[i].is_SGI,
3037                                 lq_sta->lq_info[i].is_ht40,
3038                                 lq_sta->lq_info[i].is_dup,
3039                                 lq_sta->is_green,
3040                                 lq_sta->lq_info[i].current_rate);
3041                 for (j = 0; j < IWL_RATE_COUNT; j++) {
3042                         desc += sprintf(buff+desc,
3043                                 "counter=%d success=%d %%=%d\n",
3044                                 lq_sta->lq_info[i].win[j].counter,
3045                                 lq_sta->lq_info[i].win[j].success_counter,
3046                                 lq_sta->lq_info[i].win[j].success_ratio);
3047                 }
3048         }
3049         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
3050         kfree(buff);
3051         return ret;
3052 }
3053
3054 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
3055         .read = rs_sta_dbgfs_stats_table_read,
3056         .open = open_file_generic,
3057 };
3058
3059 static ssize_t rs_sta_dbgfs_rate_scale_data_read(struct file *file,
3060                         char __user *user_buf, size_t count, loff_t *ppos)
3061 {
3062         char buff[120];
3063         int desc = 0;
3064         ssize_t ret;
3065
3066         struct iwl_lq_sta *lq_sta = file->private_data;
3067         struct iwl_priv *priv;
3068         struct iwl_scale_tbl_info *tbl = &lq_sta->lq_info[lq_sta->active_tbl];
3069
3070         priv = lq_sta->drv;
3071
3072         if (is_Ht(tbl->lq_type))
3073                 desc += sprintf(buff+desc,
3074                                 "Bit Rate= %d Mb/s\n",
3075                                 tbl->expected_tpt[lq_sta->last_txrate_idx]);
3076         else
3077                 desc += sprintf(buff+desc,
3078                                 "Bit Rate= %d Mb/s\n",
3079                                 iwl_rates[lq_sta->last_txrate_idx].ieee >> 1);
3080         desc += sprintf(buff+desc,
3081                         "Signal Level= %d dBm\tNoise Level= %d dBm\n",
3082                         priv->last_rx_rssi, priv->last_rx_noise);
3083         desc += sprintf(buff+desc,
3084                         "Tsf= 0x%llx\tBeacon time= 0x%08X\n",
3085                         priv->last_tsf, priv->last_beacon_time);
3086
3087         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
3088         return ret;
3089 }
3090
3091 static const struct file_operations rs_sta_dbgfs_rate_scale_data_ops = {
3092         .read = rs_sta_dbgfs_rate_scale_data_read,
3093         .open = open_file_generic,
3094 };
3095
3096 static void rs_add_debugfs(void *priv, void *priv_sta,
3097                                         struct dentry *dir)
3098 {
3099         struct iwl_lq_sta *lq_sta = priv_sta;
3100         lq_sta->rs_sta_dbgfs_scale_table_file =
3101                 debugfs_create_file("rate_scale_table", 0600, dir,
3102                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
3103         lq_sta->rs_sta_dbgfs_stats_table_file =
3104                 debugfs_create_file("rate_stats_table", 0600, dir,
3105                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
3106         lq_sta->rs_sta_dbgfs_rate_scale_data_file =
3107                 debugfs_create_file("rate_scale_data", 0600, dir,
3108                         lq_sta, &rs_sta_dbgfs_rate_scale_data_ops);
3109         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
3110                 debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
3111                 &lq_sta->tx_agg_tid_en);
3112
3113 }
3114
3115 static void rs_remove_debugfs(void *priv, void *priv_sta)
3116 {
3117         struct iwl_lq_sta *lq_sta = priv_sta;
3118         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
3119         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
3120         debugfs_remove(lq_sta->rs_sta_dbgfs_rate_scale_data_file);
3121         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
3122 }
3123 #endif
3124
3125 static struct rate_control_ops rs_ops = {
3126         .module = NULL,
3127         .name = RS_NAME,
3128         .tx_status = rs_tx_status,
3129         .get_rate = rs_get_rate,
3130         .rate_init = rs_rate_init,
3131         .alloc = rs_alloc,
3132         .free = rs_free,
3133         .alloc_sta = rs_alloc_sta,
3134         .free_sta = rs_free_sta,
3135 #ifdef CONFIG_MAC80211_DEBUGFS
3136         .add_sta_debugfs = rs_add_debugfs,
3137         .remove_sta_debugfs = rs_remove_debugfs,
3138 #endif
3139 };
3140
3141 int iwlagn_rate_control_register(void)
3142 {
3143         return ieee80211_rate_control_register(&rs_ops);
3144 }
3145
3146 void iwlagn_rate_control_unregister(void)
3147 {
3148         ieee80211_rate_control_unregister(&rs_ops);
3149 }
3150